The Wilmot Proviso is considered an important part of the build up to the outbreak of Civil War. It attempted to ban the extension of slavery into any states or territory acquired in the war with Mexico; however, it was repeatedly rejected in the Senate because the South had enough representatives to block such legislation from passing. The issue would be settled temporarily by the Compromise of 1850.

Grandfather clauses were established in the South during the Reconstruction era, after the Civil War, in an attempt to prevent many African-Americans from voting. In the Reconstruction era, many Southern states made laws declaring that any man voting had to pass strict literacy and property ownership tests, unless he could prove that his grandfather had been able to vote prior to the Civil War. Grandfather clauses were ruled unconstitutional in 1915.

In 1857, the Supreme Court made a decision that black Americans were inferior, not-citizens that didn’t hold equal rights to white men (regardless of free or slave status). This decision also struck a blow against new-land abolitionists, ruling that the federal government couldn’t control the legality of slavery in new federal territories.

The Thirteenth Amendment passed in 1865 at the end of the Civil War abolished slavery in the reunited Union.

Korematsu v. US upheld the coerced relocation of Japanese Americans into internment camps during World War II. Despite its controversy, a later court has never explicitly overturned it.

The 15^th Amendment granted African Americans the right to vote, after the 13^th Amendment abolishing slavery and the 14^th Amendment establishing the equal protection clause.

Loving v. Virginia struck down laws banning interracial marriage. This case was later referenced as an argument in the 2015 case Obergefell v. Hodges that legalized same-sex marriages.

Brown v. Board of Education was a case from Topeka, KS decided in 1954. It struck down separate white and black public schools, overturning Plessy v. Ferguson and the notion of “separate but equal.”

Both Congress and the Supreme Court made several attempts to ensure that African-Americans were able to freely exercise, without harassment or burden, their right to vote. But by far, the most effective of these attempts was the Voting Rights Act of 1965. The Voting Rights Act built on the protections already in place (but not always enforced) by other federal acts – including the Fifteenth and Twenty-fourth Amendments and the Civil Rights Act – but expanded these rights decisively and also granted the federal government wide latitude to support to them. In the past, most Southern states, and many in the North as well, had circumvented the Fifteenth Amendment’s requirement that all African-American males be permitted to vote, often through the passage of strict Jim Crow laws, discriminatory literacy tests at the election box, exorbitant poll taxes, and/or by holding so-called white primary elections (in which only white citizens were permitted to vote). The Voting Rights Act outlawed any and all method(s) which any level of government (national, state, or local), on the grounds of race, might use to prevent an individual from exercising their right to vote. To ensure that this Act was carried out to the fullest possible extent, the federal government contacted state and local governments directly, sending voter-registration forms into racially-discriminatory areas and requiring any alterations to the electoral process to first be approved and assessed by the federal government. The Voting Rights Act was a great success; many African-Americans, especially throughout the South, were able to reclaim their right to vote for the very first time.

The policy of affirmative action originally derives from an Executive Order passed by President Lyndon B. Johnson in 1965, in which he banned federal institutions and employees from engaging in any discriminatory practices on the basis of race, gender, or religion. Furthermore, President Johnson required these federal bodies to take active measures to prevent and stop discrimination, particularly when it came to employment decisions; simple passive acknowledgement was no longer permitted. President Johnson’s Order is therefore the basis for the affirmative action policy, which strives to ensure that all minorities, particularly those against whom society has historically discriminated, are accorded fair and equal opportunities in the realms of both employment and education. The Supreme Court has heard many cases arguing both for and against affirmative action over the years, but overall the Court has upheld the practice, although it has imposed certain definitions, requirements, and prohibitions.