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Saturday, May 16, 2020

Jim Crow laws

From Wikipedia, the free encyclopedia

Jim Crow laws were state and local laws that enforced racial segregation in the Southern United States. All were enacted in the late 19th and early 20th centuries by white Democratic-dominated state legislatures after the Reconstruction period. The laws were enforced until 1965. In practice, Jim Crow laws mandated racial segregation in all public facilities in the states of the former Confederate States of America and other states, starting in the 1870s and 1880s. Jim Crow laws were upheld in 1896 in the case of Plessy vs. Ferguson, in which the U.S. Supreme Court laid out its "separate but equal" legal doctrine for facilities for African Americans. Moreover, public education had essentially been segregated since its establishment in most of the South after the Civil War (1861–65).

The legal principle of "separate but equal" racial segregation was extended to public facilities and transportation, including the coaches of interstate trains and buses. Facilities for African Americans and Native Americans were consistently inferior and underfunded compared to the facilities for white Americans; sometimes, there were no facilities for people of color. As a body of law, Jim Crow institutionalized economic, educational, and social disadvantages for African Americans and other people of color living in the South.

Jim Crow laws and Jim Crow state constitutional provisions mandated the segregation of public schools, public places, and public transportation, and the segregation of restrooms, restaurants, and drinking fountains for whites and blacks. The U.S. military was already segregated. President Woodrow Wilson, a Southern Democrat, initiated the segregation of federal workplaces in 1913.

In 1954, segregation of public schools (state-sponsored) was declared unconstitutional by the U.S. Supreme Court under Chief Justice Earl Warren in landmark case Brown v. Board of Education. In some states, it took many years to implement this decision, while the Warren Court continued to rule against the Jim Crow laws in other cases such as Heart of Atlanta Motel, Inc. v. United States (1964). Generally, the remaining Jim Crow laws were overruled by the Civil Rights Act of 1964 and the Voting Rights Act of 1965.

Etymology

The phrase "Jim Crow Law" can be found as early as 1892 in the title of a New York Times article about Louisiana requiring segregated railroad cars. The origin of the phrase "Jim Crow" has often been attributed to "Jump Jim Crow", a song-and-dance caricature of blacks performed by white actor Thomas D. Rice in blackface, which first surfaced in 1828 and was used to satirize Andrew Jackson's populist policies. As a result of Rice's fame, "Jim Crow" by 1838 had become a pejorative expression meaning "Negro". When southern legislatures passed laws of racial segregation directed against blacks at the end of the 19th century, these statutes became known as Jim Crow laws.

Origins of Jim Crow laws

In January 1865 an amendment to the Constitution to abolish slavery in the United States was proposed by Congress, and on December 18, 1865, it was ratified as the Thirteenth Amendment formally abolishing slavery.

Cover of an early edition of "Jump Jim Crow" sheet music (circa 1832)
 
Freedmen voting in New Orleans, 1867
 
During the Reconstruction period of 1865–1877, federal laws provided civil rights protections in the U.S. South for freedmen, the African Americans who had formerly been slaves, and the minority of blacks who had been free before the war. In the 1870s, Democrats gradually regained power in the Southern legislatures, having used insurgent paramilitary groups, such as the White League and the Red Shirts, to disrupt Republican organizing, run Republican officeholders out of town, and intimidate blacks to suppress their voting. Extensive voter fraud was also used. Gubernatorial elections were close and had been disputed in Louisiana for years, with increasing violence against blacks during campaigns from 1868 onward. 

In 1877, a national Democratic Party compromise to gain Southern support in the presidential election (a corrupt bargain) resulted in the government's withdrawing the last of the federal troops from the South. White Democrats had regained political power in every Southern state. These Southern, white, Democratic Redeemer governments legislated Jim Crow laws, officially segregating black people from the white population.

Blacks were still elected to local offices throughout the 1880s, but their voting was suppressed for state and national elections. Democrats passed laws to make voter registration and electoral rules more restrictive, with the result that political participation by most blacks and many poor whites began to decrease. Between 1890 and 1910, ten of the eleven former Confederate states, starting with Mississippi, passed new constitutions or amendments that effectively disenfranchised most blacks and tens of thousands of poor whites through a combination of poll taxes, literacy and comprehension tests, and residency and record-keeping requirements. Grandfather clauses temporarily permitted some illiterate whites to vote but gave no relief to most blacks. 

Voter turnout dropped drastically through the South as a result of such measures. In Louisiana, by 1900, black voters were reduced to 5,320 on the rolls, although they comprised the majority of the state's population. By 1910, only 730 blacks were registered, less than 0.5% of eligible black men. "In 27 of the state's 60 parishes, not a single black voter was registered any longer; in 9 more parishes, only one black voter was." The cumulative effect in North Carolina meant that black voters were completely eliminated from voter rolls during the period from 1896–1904. The growth of their thriving middle class was slowed. In North Carolina and other Southern states, blacks suffered from being made invisible in the political system: "[W]ithin a decade of disfranchisement, the white supremacy campaign had erased the image of the black middle class from the minds of white North Carolinians." In Alabama tens of thousands of poor whites were also disenfranchised, although initially legislators had promised them they would not be affected adversely by the new restrictions.

Those who could not vote were not eligible to serve on juries and could not run for local offices. They effectively disappeared from political life, as they could not influence the state legislatures, and their interests were overlooked. While public schools had been established by Reconstruction legislatures for the first time in most Southern states, those for black children were consistently underfunded compared to schools for white children, even when considered within the strained finances of the postwar South where the decreasing price of cotton kept the agricultural economy at a low.

Like schools, public libraries for blacks and Native Americans were underfunded, if they existed at all, and they were often stocked with secondhand books and other resources. These facilities were not introduced for African Americans in the South until the first decade of the 20th century. Throughout the Jim Crow era, libraries were only available sporadically. Prior to the 20th century, most libraries established for African Americans were school-library combinations. Many public libraries for both European-American and African-American patrons in this period were founded as the result of middle-class activism aided by matching grants from the Carnegie Foundation.

In some cases, progressive measures intended to reduce election fraud, such as the Eight Box Law in South Carolina, acted against black and white voters who were illiterate, as they could not follow the directions. While the separation of African Americans from the white general population was becoming legalized and formalized during the Progressive Era (1890s–1920s), it was also becoming customary. For instance, even in cases in which Jim Crow laws did not expressly forbid black people to participate in sports or recreation, a segregated culture had become common.

In the Jim Crow context, the presidential election of 1912 was steeply slanted against the interests of black Americans. Most blacks still lived in the South, where they had been effectively disfranchised, so they could not vote at all. While poll taxes and literacy requirements banned many poor or illiterate Americans from voting, these stipulations frequently had loopholes that exempted European Americans from meeting the requirements. In Oklahoma, for instance, anyone qualified to vote before 1866, or related to someone qualified to vote before 1866 (a kind of "grandfather clause"), was exempted from the literacy requirement; but the only persons who had the franchise before that year were white, or European-American males. European Americans were effectively exempted from the literacy testing, whereas black Americans were effectively singled out by the law.

Woodrow Wilson was a Democrat elected from New Jersey, but he was born and raised in the South, and was the first Southern-born president of the post-Civil War period. He appointed Southerners to his Cabinet. Some quickly began to press for segregated workplaces, although the city of Washington, D.C., and federal offices had been integrated since after the Civil War. In 1913, for instance, Secretary of the Treasury William Gibbs McAdoo – an appointee of the President – was heard to express his opinion of black and white women working together in one government office: "I feel sure that this must go against the grain of the white women. Is there any reason why the white women should not have only white women working across from them on the machines?"

The Wilson administration introduced segregation in federal offices, despite much protest from African-American leaders and white progressive groups in the north and midwest. He appointed segregationist Southern politicians because of his own firm belief that racial segregation was in the best interest of black and European Americans alike. At Gettysburg on July 4, 1913, the semi-centennial of Abraham Lincoln's declaration that "all men are created equal", Wilson addressed the crowd:
How complete the union has become and how dear to all of us, how unquestioned, how benign and majestic, as state after state has been added to this, our great family of free men!
In sharp contrast to Wilson, a Washington Bee editorial wondered if the "reunion" of 1913 was a reunion of those who fought for "the extinction of slavery" or a reunion of those who fought to "perpetuate slavery and who are now employing every artifice and argument known to deceit" to present emancipation as a failed venture. Historian David W. Blight notes that the "Peace Jubilee" at which Wilson presided at Gettysburg in 1913 "was a Jim Crow reunion, and white supremacy might be said to have been the silent, invisible master of ceremonies."

In Texas, several towns adopted residential segregation laws between 1910 and the 1920s. Legal strictures called for segregated water fountains and restrooms. Jim Crow laws were a product of what had become the solidly Democratic South due to disfranchisement of blacks.

Native Americans, like African Americans, were also affected by the Jim Crow laws, especially after they were made citizens through the Indian Citizenship Act of 1924. Native American identity was especially targeted by a system that only wanted to recognize white or colored, and the government began to question the legitimacy of some tribes because they had intermarried with African Americans. The Office of Indian Affairs (OIA) employed anthropometrists to determine the blood quantum of Native Americans in the South, and declared that the only individuals who could claim Native American identity were those determined to be half- or full-blooded Native Americans, making individuals even more vulnerable to Jim Crow laws. Native Americans who were part white or light-complexioned would often pass as white to avoid the persecution of the Jim Crow laws, while family members with reddish-brown skin could not. Native Americans in the South were especially affected through their education, as schools in the native communities, like black schools, were poorly funded; some Native American children attended "colored" schools. Immediate citizenship didn't change the views that White Americans had about Native Americans, and voter suppression was a tactic that was used against Native Americans in the South. States used five basic arguments in justifying the denial of voting rights to Native Americans: (1) failure to sever tribal ties makes Native Americans ineligible; (2) "Native Americans not taxed"; (3) Native Americans that are under guardianship; (4) reservation Indians are not residents; and (5) tribal sovereignty precludes participation in state and local governments. Jim Crow laws were carried over into the West; some states did not allow Native Americans to vote, or made it difficult for them to reach the ballot boxes. A disproportionate lack of access to voter registration was often made with Native Americans having to travel excessive miles from a reservation.

Historical development

Early attempts to break Jim Crow

Sign for the "colored" waiting room at a bus station in Durham, North Carolina, May 1940
 
The Civil Rights Act of 1875, introduced by Charles Sumner and Benjamin F. Butler, stipulated a guarantee that everyone, regardless of race, color, or previous condition of servitude, was entitled to the same treatment in public accommodations, such as inns, public transportation, theaters, and other places of recreation. This Act had little effect. An 1883 Supreme Court decision ruled that the act was unconstitutional in some respects, saying Congress was not afforded control over private persons or corporations. With white southern Democrats forming a solid voting bloc in Congress, due to having outsize power from keeping seats apportioned for the total population in the South (although hundreds of thousands had been disenfranchised), Congress did not pass another civil rights law until 1957.

In 1887, Rev. W. H. Heard lodged a complaint with the Interstate Commerce Commission against the Georgia Railroad company for discrimination, citing its provision of different cars for white and black/colored passengers. The company successfully appealed for relief on the grounds it offered "separate but equal" accommodation.

In 1890, Louisiana passed a law requiring separate accommodations for colored and white passengers on railroads. Louisiana law distinguished between "white", "black" and "colored" (that is, people of mixed European and African ancestry). The law had already specified that blacks could not ride with white people, but colored people could ride with whites before 1890. A group of concerned black, colored and white citizens in New Orleans formed an association dedicated to rescinding the law. The group persuaded Homer Plessy to test it; he was a man of color who was of fair complexion and one-eighth "Negro" in ancestry.

In 1892, Plessy bought a first-class ticket from New Orleans on the East Louisiana Railway. Once he had boarded the train, he informed the train conductor of his racial lineage and took a seat in the whites-only car. He was directed to leave that car and sit instead in the "coloreds only" car. Plessy refused and was immediately arrested. The Citizens Committee of New Orleans fought the case all the way to the United States Supreme Court. They lost in Plessy v. Ferguson (1896), in which the Court ruled that "separate but equal" facilities were constitutional. The finding contributed to 58 more years of legalized discrimination against black and colored people in the United States.

In 1908 Congress defeated an attempt to introduce segregated streetcars into the capital.

Racism in the United States and defenses of Jim Crow

1904 caricature of "White" and "Jim Crow" rail cars by John T. McCutcheon. Despite Jim Crow's legal pretense that the races be "separate but equal" under the law, non-whites were given inferior facilities and treatment.
 
White Southerners encountered problems in learning free labor management after the end of slavery, and they resented black Americans, who represented the Confederacy's Civil War defeat: "With white supremacy being challenged throughout the South, many whites sought to protect their former status by threatening African Americans who exercised their new rights." White Democrats used their power to segregate public spaces and facilities in law and reestablish social dominance over blacks in the South.

One rationale for the systematic exclusion of black Americans from southern public society was that it was for their own protection. An early 20th-century scholar suggested that allowing blacks to attend white schools would mean "constantly subjecting them to adverse feeling and opinion", which might lead to "a morbid race consciousness". This perspective took anti-black sentiment for granted, because bigotry was widespread in the South after slavery became a racial caste system.

World War II and post-war era

In 1944, Associate Justice Frank Murphy introduced the word "racism" into the lexicon of U.S. Supreme Court opinions in Korematsu v. United States, 323 U.S. 214 (1944). He stated that by upholding the forced relocation of Japanese Americans during World War II, the Court was sinking into "the ugly abyss of racism". This was the first time that "racism" was used in Supreme Court opinion (Murphy used it twice in a concurring opinion in Steele v Louisville & Nashville Railway Co 323 192 (1944) issued that day). Murphy used the word in five separate opinions, but after he left the court, "racism" was not used again in an opinion for two decades. It next appeared in the landmark decision of Loving v. Virginia, 388 U.S. 1 (1967). 

Numerous boycotts and demonstrations against segregation had occurred throughout the 1930s and 1940s. The NAACP had been engaged in a series of litigation cases since the early 20th century in efforts to combat laws that disenfranchised black voters across the South. Some of the early demonstrations achieved positive results, strengthening political activism, especially in the post-World War II years. Black veterans were impatient with social oppression after having fought for the United States and freedom across the world. In 1947 K. Leroy Irvis of Pittsburgh's Urban League, for instance, led a demonstration against employment discrimination by the city's department stores. It was the beginning of his own influential political career.

After World War II, people of color increasingly challenged segregation, as they believed they had more than earned the right to be treated as full citizens because of their military service and sacrifices. The Civil Rights Movement was energized by a number of flashpoints, including the 1946 police beating and blinding of World War II veteran Isaac Woodard while he was in U.S. Army uniform. In 1948 President Harry S. Truman issued Executive Order 9981, desegregating the armed services.

As the Civil Rights Movement gained momentum and used federal courts to attack Jim Crow statutes, the white-dominated governments of many of the southern states countered by passing alternative forms of restrictions.

Decline and removal

Historian William Chafe has explored the defensive techniques developed inside the African-American community to avoid the worst features of Jim Crow as expressed in the legal system, unbalanced economic power, and intimidation and psychological pressure. Chafe says "protective socialization by blacks themselves" was created inside the community in order to accommodate white-imposed sanctions while subtly encouraging challenges to those sanctions. Known as "walking the tightrope," such efforts at bringing about change were only slightly effective before the 1920s.

However, this did build the foundation for later generations to advance racial equality and de-segregation. Chafe argued that the places essential for change to begin were institutions, particularly black churches, which functioned as centres for community-building and discussion of politics. Additionally, some all-black communities, such as Mound Bayou, Mississippi and Ruthville, Virginia served as sources of pride and inspiration for black society as a whole. Over time, pushback and open defiance of the oppressive existing laws grew, until it reached a boiling point in the aggressive, large-scale activism of the 1950s civil rights movement.

Brown v. Board of Education

In landmark case Brown v. Board of Education (1954), the U.S. Supreme Court under Chief Justice Earl Warren ruled unanimously that public school segregation was unconstitutional.

The NAACP Legal Defense Committee (a group that became independent of the NAACP) – and its lawyer, Thurgood Marshall – brought the landmark case Brown v. Board of Education of Topeka, 347 U.S. 483 (1954) before the U.S. Supreme Court under Chief Justice Earl Warren. In its pivotal 1954 decision, the Warren Court unanimously (9-0) overturned the 1896 Plessy decision. The Supreme Court found that legally mandated (de jure) public school segregation was unconstitutional. The decision had far-reaching social ramifications.

Integrating collegiate sports

Racial integration of all-white collegiate sports teams was high on the Southern agenda in the 1950s and 1960s. Involved were issues of equality, racism, and the alumni demand for the top players needed to win high-profile games. The Atlantic Coast Conference (ACC) of flagship state universities in the Southeast took the lead. First they started to schedule integrated teams from the North. Finally ACC schools--typically under pressure from boosters and civil rights groups--integrated their teams. With an alumni base that dominated local and state politics, society and business, the ACC schools were successful in their endeavor--as Pamela Grundy argues, they had learned how to win:
The widespread admiration that athletic ability inspired would help transform athletic fields from grounds of symbolic play to forces for social change, places where a wide range of citizens could publicly and at times effectively challenge the assumptions that cast them as unworthy of full participation in U.S. society. While athletic successes would not rid society of prejudice or stereotype—black athletes would continue to confront racial slurs...[minority star players demonstrated] the discipline, intelligence, and poise to contend for position or influence in every arena of national life.

Public arena

In 1955, Rosa Parks refused to give up her seat on a city bus to a white man in Montgomery, Alabama. This was not the first time this happened — for example Parks was inspired by 15 year old Claudette Colvin doing the same thing nine months earlier — but the Parks act of civil disobedience was chosen, symbolically, as an important catalyst in the growth of the Civil Rights Movement; activists built the Montgomery Bus Boycott around it, which lasted more than a year and resulted in desegregation of the privately run buses in the city. Civil rights protests and actions, together with legal challenges, resulted in a series of legislative and court decisions which contributed to undermining the Jim Crow system.

End of legal segregation

President Johnson signs the Civil Rights Act of 1964
 
The decisive action ending segregation came when Congress in bipartisan fashion overcame Southern filibusters to pass the Civil Rights Act of 1964 and the Voting Rights Act of 1965. A complex interaction of factors came together unexpectedly in the period 1954–1965 to make the momentous changes possible. The Supreme Court had taken the first initiative in Brown v. Board of Education (1954) making segregation of public schools unconstitutional. Enforcement was rapid in the North and border states, but was deliberately stopped in the South by the movement called Massive Resistance, sponsored by rural segregationists who largely controlled the state legislatures. Southern liberals, who counseled moderation, where shouted down by both sides and have limited impact. Much more significant was the Civil Rights Movement, especially the Southern Christian Leadership Conference (SCLC) headed by Martin Luther King, Jr.. It largely displaced the old, much more moderate NAACP in taking leadership roles. King organize massive demonstrations, that seized massive media attention in an era when network television news was an innovative and universally watched phenomenon.  SCLC, student activists and smaller local organizations staged demonstrations across the South. National attention focused on Birmingham, Alabama, where protesters deliberately provoked Bull Connor and his police forces by using young teenagers as demonstrators – and Connor arrested 900 on one day alone. The next day Connor unleashed billy clubs, police dogs, and high-pressure water hoses to disperse and punish the young demonstrators with a brutality that horrified the nation. It was very bad for business, and for the image of a modernizing progressive urban South. President John F. Kennedy, who had been calling for moderation, threatened to use federal troops to restore order in Birmingham. The result in Birmingham was compromise by which the new mayor opened the library, golf courses, and other city facilities to both races, against the backdrop of church bombings and assassinations.  In summer 1963, there were 800 demonstrations in 200 southern cities and towns, with over 100,000 participants, and 15,000 arrests. In Alabama in June 1963 Governor George Wallace escalated the crisis by defying court orders to admit the first two black students to the University of Alabama. Kennedy responded by sending Congress a comprehensive civil rights bill, and ordered Attorney General Robert Kennedy to file federal lawsuits against segregated schools, and to deny funds for discriminatory programs. Doctor King launched a massive march on Washington in August, 1963, bringing out 200,000 demonstrators in front of the Lincoln Memorial, the largest political assembly in the nation's history. The Kennedy administration now gave full-fledged support to the civil rights movement, but powerful southern congressman blocked any legislation.  After Kennedy was assassinated President Lyndon Johnson called for immediate passage of Kennedy civil rights legislation as a memorial to the martyred president. Johnson formed a coalition with Northern Republicans that led to passage in the House, and with the help of Republican Senate leader Everett Dirksen with passage in the Senate early in 1964. For the first time in history, the southern filibuster was broken and The Senate finally passed its version on June 19 by vote of 73 to 27.  The Civil Rights Act of 1964 was the most powerful affirmation of equal rights ever made by Congress. It guaranteed access to public accommodations such as restaurants and places of amusement, authorized the Justice Department to bring suits does desegregate facilities in schools, gave new powers to the Civil Rights Commission; and allowed federal funds to be cut off in cases of discrimination. Furthermore, racial, religious and gender discrimination was outlawed for businesses with 25 or more employees, as well as apartment houses. The South resisted until the very last moment, but as soon as the new law was signed by President Johnson on July 2, 1964, it was widely accepted across the nation. There was only a scattering of diehard opposition, typified by restaurant owner Lester Maddox in Georgia.

In January 1964, President Lyndon Johnson met with civil rights leaders. On January 8, during his first State of the Union address, Johnson asked Congress to "let this session of Congress be known as the session which did more for civil rights than the last hundred sessions combined." On June 21, civil rights workers Michael Schwerner, Andrew Goodman, and James Chaney disappeared in Neshoba County, Mississippi, where they were volunteering in the registration of African-American voters as part of the Mississippi Summer Project. The disappearance of the three activists captured national attention and the ensuing outrage was used by Johnson and civil rights activists to build a coalition of northern and western Democrats and Republicans and push Congress to pass the Civil Rights Act of 1964.

On July 2, 1964, Johnson signed the historic Civil Rights Act of 1964. It invoked the Commerce Clause to outlaw discrimination in public accommodations (privately owned restaurants, hotels, and stores, and in private schools and workplaces). This use of the Commerce Clause was upheld by Warren Court in landmark case Heart of Atlanta Motel v. United States 379 US 241 (1964).

By 1965, efforts to break the grip of state disenfranchisement by education for voter registration in southern counties had been under way for some time, but had achieved only modest success overall. In some areas of the Deep South, white resistance made these efforts almost entirely ineffectual. The murder of the three voting-rights activists in Mississippi in 1964 and the state's refusal to prosecute the murderers, along with numerous other acts of violence and terrorism against blacks, had gained national attention. Finally, the unprovoked attack on March 7, 1965, by county and state troopers on peaceful Alabama marchers crossing the Edmund Pettus Bridge en route from Selma to the state capital of Montgomery, persuaded the President and Congress to overcome Southern legislators' resistance to effective voting rights enforcement legislation. President Johnson issued a call for a strong voting rights law and hearings soon began on the bill that would become the Voting Rights Act.

The Voting Rights Act of 1965 ended legally sanctioned state barriers to voting for all federal, state and local elections. It also provided for federal oversight and monitoring of counties with historically low minority voter turnout. Years of enforcement have been needed to overcome resistance, and additional legal challenges have been made in the courts to ensure the ability of voters to elect candidates of their choice. For instance, many cities and counties introduced at-large election of council members, which resulted in many cases of diluting minority votes and preventing election of minority-supported candidates.

Influence and aftermath

Interracial marriage

Although sometimes counted among "Jim Crow laws" of the South, such statutes as anti-miscegenation laws were also passed by other states. Anti-miscegenation laws were not repealed by the Civil Rights Act of 1964, but were declared unconstitutional by the U.S. Supreme Court (the Warren Court) in a unanimous ruling Loving v. Virginia (1967). Chief Justice Earl Warren wrote in the court opinion that "the freedom to marry, or not marry, a person of another race resides with the individual, and cannot be infringed by the State."

Jury trials

The Sixth Amendment to the United States Constitution required individuals on criminal convictions to be tried by a jury of their peers. While federal law required that convictions could only granted from an unanimous jury vote for federal crimes, states were free to decide on this process for themselves. All but two states, Oregon and Louisiana, had opted for the same unanimous jury conviction requirements. Both Oregon and Louisiana allowed jury votes of at least 10-2 to decide a criminal conviction. Louisiana's law was eventually changed to require unanimous jury votes for criminal convictions for crimes after 2019, but before that point, the law was seen as a remnant of Jim Crow laws, since it allowed minority voices on a jury to be marginalized. In 2020, the Supreme Court found in Ramos v. Louisiana that unanimous jury votes are required for criminal convictions at state levels, nullifying Oregon's remaining law and overturning previous cases in Louisiana.

African-American life

An African-American man drinking at a "colored" drinking fountain in a streetcar terminal in Oklahoma City, Oklahoma, 1939

The Jim Crow laws and the high rate of lynchings in the South were major factors which led to the Great Migration during the first half of the 20th century. Because opportunities were so limited in the South, African Americans moved in great numbers to cities in Northeastern, Midwestern, and Western states to seek better lives.

Despite the hardship and prejudice of the Jim Crow era, several black entertainers and literary figures gained broad popularity with white audiences in the early 20th century. They included luminaries such as tap dancers Bill "Bojangles" Robinson and the Nicholas Brothers, jazz musicians such as Louis Armstrong, Duke Ellington and Count Basie, and the actress Hattie McDaniel. In 1939 McDaniel was the first black person to receive an Academy Award when she won the Best Supporting Actress Oscar for her performance as Mammy in Gone with the Wind.

African-American athletes faced much discrimination during the Jim Crow period. White opposition led to their exclusion from most organized sporting competitions. The boxers Jack Johnson and Joe Louis (both of whom became world heavyweight boxing champions) and track and field athlete Jesse Owens (who won four gold medals at the 1936 Summer Olympics in Berlin) earned fame during this era. In baseball, a color line instituted in the 1880s had informally barred blacks from playing in the major leagues, leading to the development of the Negro Leagues, which featured many fine players. A major breakthrough occurred in 1947, when Jackie Robinson was hired as the first African American to play in Major League Baseball; he permanently broke the color bar. Baseball teams continued to integrate in the following years, leading to the full participation of black baseball players in the Major Leagues in the 1960s.

Later court cases

In 1971, the U.S. Supreme Court (the Burger Court), in Swann v. Charlotte-Mecklenburg Board of Education, upheld desegregation busing of students to achieve integration.

Interpretation of the Constitution and its application to minority rights continues to be controversial as Court membership changes. Observers such as Ian F. Lopez believe that in the 2000s, the Supreme Court has become more protective of the status quo.

Remembrance

Ferris State University in Big Rapids, Michigan, houses the Jim Crow Museum of Racist Memorabilia, an extensive collection of everyday items that promoted racial segregation or presented racial stereotypes of African Americans, for the purpose of academic research and education about their cultural influence.

Portuguese discoveries

From Wikipedia, the free encyclopedia
 
The Cantino planisphere, made by an anonymous cartographer in 1502, shows the world as it was understood by Europeans after their great explorations at the end of the fifteenth century.
 
Portuguese discoveries (Portuguese: Descobrimentos portugueses) are the numerous territories and maritime routes discovered by the Portuguese as a result of their intensive maritime exploration during the 15th and 16th centuries. Portuguese sailors were at the vanguard of European overseas exploration, discovering and mapping the coasts of Africa, Canada, Asia, and Brazil, in what became known as the Age of Discovery. Methodical expeditions started in 1419 along West Africa's coast under the sponsorship of prince Henry the Navigator, with Bartolomeu Dias reaching the Cape of Good Hope and entering the Indian Ocean in 1488. Ten years later, in 1498, Vasco da Gama led the first fleet around Africa to India, arriving in Calicut and starting a maritime route from Portugal to India. Portuguese explorations then proceeded to southeast Asia, where they reached Japan in 1542, forty-four years after their first arrival in India. In 1500, the Portuguese nobleman Pedro Álvares Cabral became the first European to discover Brazil.

Origins

Vasco da Gama lands in Calicut on May 20th 1498.
 
In 1139 the Kingdom of Portugal achieved independence from León, having doubled its area with the Reconquista under Afonso Henriques

In 1297, king Denis of Portugal took personal interest in the development of exports, having organized the export of surplus production to European countries. On May 10, 1293, he instituted a maritime insurance fund for Portuguese traders living in the County of Flanders, which were to pay certain sums according to tonnage, accrued to them when necessary. Wine and dried fruits from Algarve were sold in Flanders and England, salt from Setúbal and Aveiro was a profitable export to northern Europe, and leather and kermes, a scarlet dye, were also exported. Portuguese imported armors and munitions, fine clothes and several manufactured products from Flanders and Italy.

In 1317 king Denis made an agreement with Genoese merchant sailor Manuel Pessanha (Pessagno), appointing him first Admiral with trade privileges with his homeland in return for twenty war ships and crews, with the goal of defending the country against Muslim pirate raids, thus laying the basis for the Portuguese Navy and establishment of a Genoese merchant community in Portugal. Forced to reduce their activities in the Black Sea, the Republic of Genoa had turned to north African trade of wheat, olive oil (valued also as energy source) and a search for gold – navigating also into the ports of Bruges (Flanders) and England. Genoese and Florentine communities established since then in Portugal, who profited from the enterprise and financial experience of these rivals of the Republic of Venice.

In the second half of the fourteenth century outbreaks of bubonic plague led to severe depopulation: the economy was extremely localized in a few towns, and migration from the country led to agricultural land being abandoned, resulting in an increase in rural unemployment. Only the sea offered alternatives, with most people settling in fishing and trading coastal areas. Between 1325–1357 Afonso IV of Portugal granted public funding to raise a proper commercial fleet and ordered the first maritime explorations, with the help of Genoese, under command of admiral Manuel Pessanha. In 1341 the Canary Islands, already known to Genoese, were officially discovered under the patronage of the Portuguese king, but in 1344 Castile disputed them, further propelling the Portuguese navy efforts.

Atlantic exploration (1415–1488)

Prince Henry the Navigator, generally credited as the driving force behind Portuguese maritime exploration.
 
In 1415, Ceuta was occupied by the Portuguese aiming to control navigation of the African coast, moved by expanding Christianity with the avail of the Pope and a desire of the unemployed nobility for epic acts of war after the reconquista. Young prince Henry the Navigator was there and became aware of profit possibilities in the Saharan trade routes. Governor of the rich Order of Christ since 1420 and holding valuable monopolies on resources in Algarve, he invested in sponsoring voyages down the coast of Mauritania, gathering a group of merchants, shipowners, stakeholders and participants interested in the sea lanes. Later his brother Prince Pedro, granted him a royal monopoly of all profits from trading within the areas discovered. Soon the Atlantic islands of Madeira (1420) and Azores (1427) were reached. There, wheat and later sugarcane were cultivated, like in Algarve, by the Genoese, becoming profitable activities. This helped them become wealthier.

Henry the Navigator took the lead role in encouraging Portuguese maritime exploration until his death in 1460. At the time, Europeans did not know what lay beyond Cape Bojador on the African coast. Henry wished to know how far the Muslim territories in Africa extended, and whether it was possible to reach Asia by sea, both to reach the source of the lucrative spice trade and perhaps to join forces with the long-lost Christian kingdom of Prester John that was rumoured to exist somewhere in the "Indies".

In 1419 two of Henry's captains, João Gonçalves Zarco and Tristão Vaz Teixeira were driven by a storm to Madeira, an uninhabited island off the coast of Africa which had probably been known to Europeans since the 14th century. In 1420 Zarco and Teixeira returned with Bartolomeu Perestrelo and began Portuguese settlement of the islands. A Portuguese attempt to capture Grand Canary, one of the nearby Canary Islands, which had been partially settled by Spaniards in 1402 was unsuccessful and met with protestations from Castile. Although the exact details are uncertain, cartographic evidence suggests the Azores were probably discovered in 1427 by Portuguese ships sailing under Henry's direction, and settled in 1432, suggesting that the Portuguese were able to navigate at least 745 miles (1,200 km) from the Portuguese coast.

At around the same time as the unsuccessful attack on the Canary Islands, the Portuguese began to explore the North African coast. Sailors feared what lay beyond Cape Bojador, and whether it was possible to return once it was passed. In 1434 one of Prince Henry's captains, Gil Eanes, passed this obstacle. Once this psychological barrier had been crossed, it became easier to probe further along the coast. Westward exploration continued over the same period: Diogo Silves discovered the Azores island of Santa Maria in 1427 and in the following years Portuguese discovered and settled the rest of the Azores. Within two decades of exploration, Portuguese ships bypassed the Sahara.

The caravel ship introduced in the mid-15th century which aided Portuguese exploration

Henry suffered a serious setback in 1437 after the failure of an expedition to capture Tangier, having encouraged his brother, King Edward, to mount an overland attack from Ceuta. The Portuguese army was defeated and only escaped destruction by surrendering Prince Ferdinand, the king's youngest brother. After the defeat at Tangier, Henry retired to Sagres on the southern tip of Portugal where he continued to direct Portuguese exploration until his death in 1460. 

In 1443 Prince Pedro, Henry's brother, granted him the monopoly of navigation, war and trade in the lands south of Cape Bojador. Later this monopoly would be enforced by the Papal bulls Dum Diversas (1452) and Romanus Pontifex (1455), granting Portugal the trade monopoly for the newly discovered countries, laying the basis for the Portuguese empire. 

A major advance which accelerated this project was the introduction of the caravel in the mid-15th century, a ship that could be sailed closer to the wind than any other in operation in Europe at the time. Using this new maritime technology, Portuguese navigators reached ever more southerly latitudes, advancing at an average rate of one degree a year. Senegal and Cape Verde Peninsula were reached in 1445. The first feitoria trade post overseas was established then under Henry's directions, in 1445 on the island of Arguin off the coast of Mauritania, to attract Muslim traders and monopolize the business in the routes traveled in North Africa, starting the chain of Portuguese feitorias along the coast. In 1446, Álvaro Fernandes pushed on almost as far as present-day Sierra Leone and the Gulf of Guinea was reached in the 1460s.

Exploration after Prince Henry

An illustration of the padrão Diogo Cão erected at Cape St. Mary, Angola.

As a result of the first meager returns of the African explorations, in 1469 king Afonso V granted the monopoly of trade in part of the Gulf of Guinea to merchant Fernão Gomes, for an annual payment of 200,000 reals. Gomes was also required to explore 100 leagues (480 km) of the coast each year for five years. He employed explorers João de Santarém, Pedro Escobar, Lopo Gonçalves, Fernão do Pó, and Pedro de Sintra, and exceeded the requirement. Under his sponsorship, Portuguese explorers crossed the Equator into the Southern Hemisphere and found the islands of the Gulf of Guinea, including São Tomé and Príncipe.

In 1471, Gomes' explorers reached Elmina on the Gold Coast (present day Ghana), and discovered a thriving gold trade between the natives and visiting Arab and Berber traders. Gomes established his own trading post there, which became known as “A Mina” ("The Mine"). Trade between Elmina and Portugal grew in the next decade. In 1481, the recently crowned João II decided to build São Jorge da Mina fort (Elmina Castle) and factory to protect this trade, which was then held again as a royal monopoly.

In 1482, Diogo Cão discovered the Congo River. In 1486, Cão continued to Cape Cross, in present-day Namibia, near the Tropic of Capricorn.

Iberian mare clausum claims during the Age of Discovery.
 
In 1488, Bartolomeu Dias rounded the Cape of Good Hope on the southern tip of Africa, disproving the view that had existed since Ptolemy that the Indian Ocean was separate from the Atlantic. Also at this time, Pêro da Covilhã reached India via Egypt and Yemen, and visited Madagascar. He recommended further exploration of the southern route.

As the Portuguese explored the coastlines of Africa, they left behind a series of padrões, stone crosses inscribed with the Portuguese coat of arms marking their claims, and built forts and trading posts. From these bases, the Portuguese engaged profitably in the slave and gold trades. Portugal enjoyed a virtual monopoly of the Atlantic slave trade for over a century, exporting around 800 slaves annually. Most were brought to the Portuguese capital Lisbon, where it is estimated black Africans came to constitute 10 percent of the population.

Tordesillas division of the world (1492)

The 1494 Tordesilhas Treaty meridian dividing the world between Portugal and Castille/Spain (purple) and the Moluccas antimeridian (green), set at the Treaty of Zaragoza, 1529

In 1492 Christopher Columbus's discovery for Spain of the New World, which he believed to be Asia, led to disputes between the Spanish and Portuguese. These were eventually settled by the Treaty of Tordesillas in 1494 which divided the world outside of Europe in an exclusive duopoly between the Portuguese and the Spanish, along a north–south meridian 370 leagues, or 970 miles (1,560 km), west of the Cape Verde islands. However, as it was not possible at the time to correctly measure longitude, the exact boundary was disputed by the two countries until 1777.

The completion of these negotiations with Spain is one of several reasons proposed by historians for why it took nine years for the Portuguese to follow up on Dias's voyage to the Cape of Good Hope, though it has also been speculated that other voyages were, in fact, taking place in secret during this time. Whether or not this was the case, the long-standing Portuguese goal of finding a sea route to Asia was finally achieved in a ground-breaking voyage commanded by Vasco da Gama.

Reaching India and Brazil (1497–1500)

The route followed in Vasco da Gama's first voyage (1497–1499)
 
The squadron of Vasco da Gama left Portugal in 1497, rounded the Cape and continued along the coast of East Africa, where a local pilot was brought on board who guided them across the Indian Ocean, reaching Calicut in western India in May 1498. The second voyage to India was dispatched in 1500 under Pedro Álvares Cabral. While following the same south-westerly route as Gama across the Atlantic Ocean, Cabral made landfall on the Brazilian coast. This was probably an accidental discovery, but it has been speculated that the Portuguese secretly knew of Brazil's existence and that it lay on their side of the Tordesillas line. Cabral recommended to the Portuguese King that the land be settled, and two follow up voyages were sent in 1501 and 1503. The land was found to be abundant in pau-brasil, or brazilwood, from which it later inherited its name, but the failure to find gold or silver meant that for the time being Portuguese efforts were concentrated on India.

On 8 July 1497 the fleet, consisting of four ships and a crew of 170 men, left Lisbon The travel led by Vasco da Gama to Calicut was the starting point for deployment of Portuguese in the African east coast and in the Indian Ocean. The first contact occurred on 20 May 1498. After some conflict, he got an ambiguous letter for trade with the Zamorin of Calicut, leaving there some men to establish a trading post. Since then explorations lost private support, taking place under the exclusive patronage of the Portuguese Crown. Shortly after, the Casa da Índia was established in Lisbon to administer the royal monopoly of navigation and trade.

Indian Ocean explorations (1497–1542)

The carrack Santa Catarina do Monte Sinai and other Portuguese Navy' ships in the 16th century.

The aim of Portugal in the Indian Ocean was to ensure the monopoly of the spice trade. Taking advantage of the rivalries that pitted Hindus against Muslims, the Portuguese established several forts and trading posts between 1500 and 1510. In East Africa, small Islamic states along the coast of Mozambique, Kilwa, Brava, Sofala and Mombasa were destroyed, or became either subjects or allies of Portugal. Pêro da Covilhã had reached Ethiopia, traveling secretly overland, as early as 1490; a diplomatic mission reached the ruler of that nation on October 19, 1520.

In 1500 the second fleet to India who came to discover Brazil explored the East African coast, where Diogo Dias discovered the island that he named St. Lawrence, later known as Madagascar. This fleet, commanded by Pedro Álvares Cabral, arrived at Calicut in September, where the first trade agreement in India was signed. For a short time a Portuguese factory was installed there, but was attacked by Muslims on December 16 and several Portuguese, including the scribe Pêro Vaz de Caminha, died. After bombarding Calicut as a retaliation, Cabral went to rival Kochi

Profiting from the rivalry between the Maharaja of Kochi and the Zamorin of Calicut, the Portuguese were well received and seen as allies, getting a permit to build a fort (Fort Manuel) and a trading post that was the first European settlement in India. There in 1503 they built the St. Francis Church. In 1502 Vasco da Gama took the island of Kilwa on the coast of Tanzania, where in 1505 the first fort of Portuguese East Africa was built to protect ships from the East Indian trade. 

In 1505 king Manuel I of Portugal appointed Francisco de Almeida first Viceroy of Portuguese India for a three-year period, starting the Portuguese government in the east, headquartered at Kochi. That year the Portuguese conquered Kannur where they founded St. Angelo Fort. Lourenço de Almeida arrived in Ceylon (modern Sri Lanka), where he discovered the source of cinnamon. Finding it divided into seven rival kingdoms, he established a defense pact with the kingdom of Kotte and extended the control in coastal areas, where in 1517 was founded the fortress of Colombo.

In 1506 a Portuguese fleet under the command of Tristão da Cunha and Afonso de Albuquerque, conquered Socotra at the entrance of the Red Sea and Muscat in 1507, having failed to conquer Ormuz, following a strategy intended to close the entrances to the Indian Ocean. That same year, fortresses were built in the Island of Mozambique and Mombasa on the Kenyan coast. Madagascar was partly explored by Tristão da Cunha and in the same year Mauritius was discovered.

The Portuguese in South Asia in the 16th & 17th centuries.
Light Green - Territories conquered or ceded.
Dark Green - Allies or under influence.
Yellow - Main Factorys

In 1509, the Portuguese won the sea Battle of Diu against the combined forces of the Ottoman Sultan Beyazid II, Sultan of Gujarat, Mamlûk Sultan of Cairo, Samoothiri Raja of Kozhikode, Venetian Republic, and Ragusan Republic (Dubrovnik). The Portuguese victory was critical for its strategy of control of the Indian Sea: Turks and Egyptians withdraw their navies from India, leaving the seas to the Portuguese, setting its trade dominance for almost a century, and greatly assisting the growth of the Portuguese Empire. It marked also the beginning of the European colonial dominance in Asia. A second Battle of Diu in 1538 finally ended Ottoman ambitions in India and confirmed Portuguese hegemony in the Indian Ocean.

Under the government of Albuquerque, Goa was taken from the Bijapur sultanate in 1510 with the help of Hindu privateer Timoji. Coveted for being the best port in the region, mainly for the commerce of Arabian horses for the Deccan sultanates, it allowed to move on from the initial guest stay in Cochin. Despite constant attacks, Goa became the seat of the Portuguese government, under the name of Estado da India (State of India), with the conquest triggering compliance of neighbour kingdoms: Gujarat and Calicut sent embassies, offering alliances and grants to fortify. Albuquerque began that year in Goa the first Portuguese mint in India, taking the opportunity to announce the achievement.

Southeast Asia expeditions

Anonymous map c.1550 of Eastern Africa, Asia and Western Oceania
 
In April 1511 Albuquerque sailed to Malacca in modern-day Malaysia, the most important eastern point in the trade network, where Malay met Gujarati, Chinese, Japanese, Javanese, Bengali, Persian and Arabic traders, described by Tomé Pires as invaluable. The port of Malacca became then the strategic base for Portuguese trade expansion with China and Southeast Asia, under the Portuguese rule in India with its capital at Goa. To defend the city a strong fort was erected, called the "A Famosa", where one of its gates still remains today. Knowing of Siamese ambitions over Malacca, Albuquerque sent immediately Duarte Fernandes on a diplomatic mission to the kingdom of Siam (modern Thailand), where he was the first European to arrive, establishing amicable relations between both kingdoms. In November that year, getting to know the location of the so-called "Spice Islands" in the Moluccas, he sent an expedition led by António de Abreu to find them, arriving in early 1512. Abreu went by Ambon while deputy commander Francisco Serrão came forward to Ternate, were a Portuguese fort was allowed. That same year, in Indonesia, the Portuguese took Makassar, reaching Timor in 1514. Departing from Malacca, Jorge Álvares came to southern China in 1513. This visit followed the arrival in Guangzhou, where trade was established. Later a trading post at Macau would be established.


The Portuguese empire expanded into the Persian Gulf as Portugal contested control of the spice trade with the Ottoman Empire. In 1515, Afonso de Albuquerque conquered the Huwala state of Hormuz at the head of the Persian Gulf, establishing it as a vassal state. Aden, however, resisted Albuquerque's expedition in that same year, and another attempt by Albuquerque's successor Lopo Soares de Albergaria in 1516, before capturing Bahrain in 1521, when a force led by António Correia defeated the Jabrid King, Muqrin ibn Zamil. In a shifting series of alliances, the Portuguese dominated much of the southern Persian Gulf for the next hundred years. With the regular maritime route linking Lisbon to Goa since 1497, the island of Mozambique became a strategic port, and there was built Fort São Sebastião and a hospital. In the Azores, the Islands Armada protected the ships en route to Lisbon. 

In 1525, after Fernão de Magalhães's expedition (1519–1522), Spain under Charles V sent an expedition to colonize the Moluccas islands, claiming that they were in his zone of the Treaty of Tordesillas, since there was not a set limit to the east. García Jofre de Loaísa expedition reached the Moluccas, docking at Tidore. The conflict with the Portuguese already established in nearby Ternate was inevitable, starting nearly a decade of skirmishes. An agreement was reached only with the Treaty of Zaragoza (1529), attributing the Moluccas to Portugal and the Philippines to Spain.

In 1530, John III organized the colonization of Brazil around 15 capitanias hereditárias ("hereditary captainships"), that were given to anyone who wanted to administer and explore them, to overcome the need to defend the territory, since an expedition under the command of Gonçalo Coelho in 1503, found the French making incursions on the land. That same year, there was a new expedition from Martim Afonso de Sousa with orders to patrol the whole Brazilian coast, banish the French, and create the first colonial towns: São Vicente on the coast, and São Paulo on the border of the altiplane. From the 15 original captainships, only two, Pernambuco and São Vicente, prospered. With permanent settlement came the establishment of the sugar cane industry and its intensive labor demands which were met with Native American and later African slaves.

In 1534 Gujarat was occupied by the Mughals and the Sultan Bahadur Shah of Gujarat was forced to sign the Treaty of Bassein (1534) with the Portuguese, establishing an alliance to regain the country, giving in exchange Daman, Diu, Mumbai and Bassein. In 1538 the fortress of Diu is again surrounded by Ottoman ships. Another siege failed in 1547 putting an end to the Ottoman ambitions, confirming the Portuguese hegemony. 

Portuguese ruler of Pegu riding an Elephant.
 
In 1542 Jesuit missionary Francis Xavier arrived in Goa at the service of king John III of Portugal, in charge of an Apostolic Nunciature. At the same time Francisco Zeimoto, António Mota, and other traders arrived in Japan for the first time. According to Fernão Mendes Pinto, who claimed to be in this journey, they arrived at Tanegashima, where the locals were impressed by firearms, which would be immediately made by the Japanese on a large scale. In 1557 the Chinese authorities allowed the Portuguese to settle in Macau through an annual payment, creating a warehouse in the triangular trade between China, Japan and Europe. In 1570 the Portuguese bought a Japanese port where they founded the city of Nagasaki, thus creating a trading center for many years was the port from Japan to the world.

Portugal established trading ports at far-flung locations like Goa, Ormuz, Malacca, Kochi, the Maluku Islands, Macau, and Nagasaki. Guarding its trade from both European and Asian competitors, Portugal dominated not only the trade between Asia and Europe, but also much of the trade between different regions of Asia, such as India, Indonesia, China, and Japan. Jesuit missionaries, such as the Basque Francis Xavier, followed the Portuguese to spread Roman Catholic Christianity to Asia with mixed success.

Map of Portuguese discoveries and explorations (1415–1543)

Portuguese discoveries and explorations: first arrival places and dates; main Portuguese spice trade 
routes in the Indian Ocean (blue); territories claimed during King John III rule (c. 1536) (green); 
Main Factorys (orange)

Portuguese nautical science

The successive expeditions and experience of the pilots led to a fairly rapid evolution of Portuguese nautical science, creating an elite of astronomers, navigators, mathematicians and cartographers, among them stood Pedro Nunes with studies on how to determine the latitudes by the stars and João de Castro.

Ships

Portuguese "Armada" fleet in 1507, Lisuarte de Abreu
 
Until the 15th century, the Portuguese were limited to cabotage navigation using barques and barinels (ancient cargo vessels used in the Mediterranean). These boats were small and fragile, with only one mast with a fixed quadrangular sail and did not have the capabilities to overcome the navigational difficulties associated with southward oceanic exploration, as the strong winds, shoals and strong ocean currents easily overwhelmed their abilities. They are associated with the earliest discoveries, such as the Madeira Islands, the Azores, the Canaries, and to the early exploration of the northwest African coast as far south as Arguim in the current Mauritania.

The ship that truly launched the first phase of the Portuguese discoveries along the African coast was the caravel, a development based on existing fishing boats. They were agile and easier to navigate, with a tonnage of 50 to 160 tons and 1 to 3 masts, with lateen triangular sails allowing luffing. The caravel benefited from a greater capacity to tack. The limited capacity for cargo and crew were their main drawbacks, but have not hindered its success. Among the famous caravels are Berrio and Anunciação. 

With the start of long oceanic sailing also large ships developed. "Nau" was the Portuguese archaic synonym for any large ship, primarily merchant ships. Due to the piracy that plagued the coasts, they began to be used in the navy and were provided with canon windows, which led to the classification of "naus" according to the power of its artillery. They were also adapted to the increasing maritime trade: from 200 tons capacity in the 15th century to 500, they become impressive in the 16th century, having usually two decks, stern castles fore and aft, two to four masts with overlapping sails. In India travels in the sixteenth century there were also used carracks, large merchant ships with a high edge and three masts with square sails, that reached 2000 tons.

Celestial navigation

Ephemeris by Abraham Zacuto in Almanach Perpetuum, 1496

In the thirteenth century celestial navigation was already known, guided by the sun position. For celestial navigation the Portuguese, like other Europeans, used Arab navigation tools, like the astrolabe and quadrant, which they made easier and simpler. They also created the cross-staff, or cane of Jacob, for measuring at sea the height of the sun and other stars. The Southern Cross become a reference upon arrival at the Southern hemisphere by João de Santarém and Pedro Escobar in 1471, starting the celestial navigation on this constellation. But the results varied throughout the year, which required corrections. 

To this the Portuguese used the astronomical tables (Ephemeris), precious tools for oceanic navigation, which have experienced a remarkable diffusion in the fifteenth century. These tables revolutionized navigation, allowing to calculate latitude. The tables of the Almanach Perpetuum, by astronomer Abraham Zacuto, published in Leiria in 1496, were used along with its improved astrolabe, by Vasco da Gama and Pedro Álvares Cabral.

Sailing techniques

Map of the five major oceanic gyres

Besides coastal exploration, Portuguese also made trips off in the ocean to gather meteorological and oceanographic information (in these were discovered the archipelagos of Madeira and the Azores, and Sargasso Sea). The knowledge of wind patterns and currents – the trade winds and the oceanic gyres in the Atlantic, and the determination of latitude led to the discovery of the best ocean route back from Africa: crossing the Central Atlantic to the latitude of the Azores, using the permanent favorable winds and currents that spin clockwise in the Northern Hemisphere because of atmospheric circulation and the effect of Coriolis, facilitating the way to Lisbon and thus enabling the Portuguese venturing increasingly farther from shore, the maneuver that became known as "Volta do mar". In 1565, the application of this principle in the Pacific Ocean led the Spanish discovering the Manila Galleon trade route.

Cartography

Pre-mercator navigation chart of the Coast of Africa (1571), by Fernão Vaz Dourado (Torre do Tombo, Lisbon)

It is thought that Jehuda Cresques, son of the Catalan cartographer Abraham Cresques has been one of the notable cartographers at the service of Prince Henry. However, the oldest signed Portuguese sea chart is a Portolan made by Pedro Reinel in 1485 representing Western Europe and parts of Africa, reflecting the explorations made by Diogo Cão. Reinel was also author of the first nautical chart known with an indication of latitudes in 1504 and the first representation of a Wind rose.

With his son, cartographer Jorge Reinel and Lopo Homem, they participated in the making of the atlas known as "Lopo Homem-Reinés Atlas" or "Miller Atlas", in 1519. They were considered the best cartographers of their time, with Emperor Charles V wanting them to work for him. In 1517 King Manuel I of Portugal handed Lopo Homem a charter giving him the privilege to certify and amend all compass needles in vessels. 

In the third phase of the former Portuguese nautical cartography, characterized by the abandonment of the influence of Ptolemy's representation of the East and more accuracy in the representation of lands and continents, stands out Fernão Vaz Dourado (Goa ~ 1520 – ~ 1580), giving him a reputation as one of the best cartographers of the time. Many of his charts are large scale.

Inequality (mathematics)

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