After the American Civil War and the abolition of slavery in the 1860s, the Reconstruction Amendments to the United States Constitution sought to secure the rights of African Americans. While for a short time, African Americans voted and held political office, they were soon deprived of civil rights, often under Jim Crow laws, and subjected to discrimination and sustained violence. Over the following century, various efforts were made by African Americans to secure their legal rights. Between 1955 and 1968, acts of nonviolent protest and civil disobedience produced crisis situations and productive dialogues between activists and government authorities. Federal, state, and local governments, businesses, and communities often had to respond immediately to these situations, which highlighted the inequities faced by African Americans. The lynching of Emmett Till and the visceral response to his mother's decision to have an open-casket funeral mobilized the African-American community nationwide. Forms of protest and/or civil disobedience included boycotts such as the successful Montgomery Bus Boycott (1955–56) in Alabama; "sit-ins" such as the influential Greensboro sit-ins (1960) in North Carolina and successful Nashville sit-ins in Tennessee; marches, such as the 1963 Birmingham Children's Crusade and 1965 Selma to Montgomery marches (1965) in Alabama; and a wide range of other nonviolent activities.
Moderates in the movement worked with Congress to achieve the passage of several significant pieces of federal legislation overturning discriminatory practices. The Civil Rights Act of 1964 expressly banned discrimination based on race, color, religion, sex, or national origin in employment practices; ended unequal application of voter registration requirements; and prohibited racial segregation in schools, at the workplace, and in public accommodations. The Voting Rights Act of 1965 restored and protected voting rights for minorities by authorizing federal oversight of registration and elections in areas with a historic under-representation of minorities as voters. The Fair Housing Act of 1968 banned discrimination in the sale or rental of housing. African Americans re-entered politics in the South, and across the country young people were inspired to take action.
From 1964 through 1970, a wave of inner-city riots in black communities undercut support from the white middle class, but increased support from private foundations. The emergence of the Black Power movement, which lasted from about 1965 to 1975, challenged the established black leadership for its cooperative attitude and its practice of nonviolence, and instead demanding that, in addition to the new laws gained through the nonviolent movement, political and economic self-sufficiency be built in the black community.
Many popular representations of the movement are centered on the charismatic leadership and philosophy of Martin Luther King Jr., who won the 1964 Nobel Peace Prize for his role in the movement. However, some scholars note that the movement was too diverse to be credited to any one person, organization, or strategy.
Before the American Civil War, almost four million blacks were enslaved in the South, only white men of property could vote, and the Naturalization Act of 1790 limited U.S. citizenship to whites only. Following the Civil War, three constitutional amendments were passed, including the 13th Amendment (1865) that ended slavery; the 14th Amendment (1868) that gave African-Americans citizenship, adding their total population of four million to the official population of southern states for Congressional apportionment; and the 15th Amendment (1870) that gave African-American males the right to vote (only males could vote in the U.S. at the time). From 1865 to 1877, the United States underwent a turbulent Reconstruction Era trying to establish free labor and civil rights of freedmen in the South after the end of slavery. Many whites resisted the social changes, leading to insurgent movements such as the Ku Klux Klan, whose members attacked black and white Republicans to maintain white supremacy. In 1871, President Ulysses S. Grant, the U.S. Army, and U.S. Attorney General Amos T. Akerman, initiated a campaign to repress the KKK under the Enforcement Acts. Some states were reluctant to enforce the federal measures of the act; by the early 1870s, other white supremacist and paramilitary groups arose that violently opposed African-American legal equality and suffrage. However, if the states failed to implement the acts, the laws allowed the Federal Government to get involved. Many Republican governors were afraid of sending black militia troops to fight the Klan for fear of war.