The Jim Crow laws were state and local racial segregation laws enacted after the Reconstruction period in Southern United States that continued in force until 1965 mandating de jure racial segregation in all public facilities in Southern U.S. states (of the former Confederacy), starting in 1890 with a "separate but equal" status for African Americans.
Conditions for African Americans were consistently inferior and underfunded compared to those provided for white Americans.
Jim Crow laws 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 also segregated, as were federal workplaces, initiated in 1913 under Democrat President Woodrow Wilson, the first Southern president elected since 1856. His administration practiced overt racial discrimination in hiring, requiring candidates to submit photos.
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 1832. By 1838, as a result of Rice's fame, "Jim Crow" had become a pejorative expression meaning "Negro".
By 1858, the Republicans dominated nearly all Northern states. The Republican Party first came to power in 1860 with the election of Lincoln to the Presidency and Republicans in control of Congress and again, the Northern states. It oversaw the preserving of the union, the end of slavery, and the provision of equal rights to all men in the American Civil War and Reconstruction.
During the Reconstruction period of 1865–1877, federal law passed by the Republican-led Congress provided civil rights protection in the U.S. South for freedmen, the African Americans who had formerly been slaves, and former free blacks.
In the 1870s, Democrats gradually regained power in the Southern legislatures, having used insurgent paramilitary groups to disrupt Republican organizing, run Republican officeholders out of town, and intimidate blacks to suppress their voting. Extensive voter fraud was also used.
In 1877, a national Democrat Party compromise to gain Southern support in the presidential election 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, Democrat governments legislated Jim Crow laws, officially segregating black people from the white population.
Read more here