What was the main cause for the end of reconstruction

Compromise of 1877

Explanation: The Compromise of 1876 effectively ended the Reconstruction era. Southern Democrats' promises to protect civil and political rights of blacks were not kept, and the end of federal interference in southern affairs led to widespread disenfranchisement of blacks voters

affirmative action refers to the policies that take gender, race, or ethnicity into account in order to promote equal opportunity.

employers subject to title vii are prohibited from taking race or sex into account in any employment decisions. aa is a penalty for having any job group substantially statistically "underutilized" in any race or either sex. the employer must take steps to eliminate the underutilization, then stop, ending its aa efforts