Radical Reconstruction ended in 1877 due to several factors. One major factor was the disputed 1876 presidential election between Republican Rutherford B. Hayes and Democrat Samuel Tilden. Tilden had won the popular vote, but the electoral college vote was disputed. In a compromise known as the Hayes-Tilden Compromise, Hayes was awarded the presidency in exchange for the withdrawal of federal troops from the South, effectively ending Reconstruction.
Additionally, white supremacist groups, such as the Ku Klux Klan, used violence and intimidation tactics to suppress the Black vote and reclaim political power in the South. This led to the rise of conservative Democrats who opposed the Radical Republicans and their policies of racial equality and black suffrage.
As a result, Northern support for Reconstruction waned, and the federal government gradually withdrew its military presence from the South, leaving Southern states to enforce their own laws and policies. This allowed for the implementation of Jim Crow laws and other forms of institutionalized racism and discrimination against African Americans, marking the end of Radical Reconstruction.