How and why did white southerners take away African Americans' right to vote and adopt ""Jim Crow"" segregation laws at the end of the nineteenth century?

White southerners sought to protect their privileged position by adopting the so-called "Jim Crow" laws.

Explanation:

The "Jim Crow" laws were a series of local and state laws that enforced racial segregation in all public facilities and spaces in the southern United States, from the end of the 19th century until they were ruled illegal by the Civil Rights Act of 1964. They were named so after a song and dance called "Jump Jim Crow", which was performed in blackface by white minstrel Thomas Rickface during the mid 19th century. He became famous for his performance, and "Jim Crow" came to be used as a derogative term for African-Americans.

With the end of the Civil War (1861-1865), slavery was declared illegal and all former slaves gained their freedom and rights as citizens of the United States. White southerners were angry after the defeat of the Confederacy, and they felt threatened by African-Americans, who represented a sizable minority in the southern states. White southerners sought to protect their privileged position by adopting the so-called "Jim Crow" laws. These laws segregated public spaces by establishing separate facilities for African-Americans, and limited their civil rights, like voting.