n [ U ]
the period of about ten years after the American Civil War during which the Confederate States were brought back into the US. US political and military forces controlled and punished the southern states. Laws were passed making slavery illegal and giving African Americans the right to vote and hold public office. White Southerners were upset by many Reconstruction practices, such as unusual elections that put former slaves in state governments. This was one cause of the growth of the Ku Klux Klan .