Final answer:
Congress did not pass civil rights legislation from the 1870s to the late 1950s mainly because those in power were unaware, unconcerned, or strongly opposed.
Step-by-step explanation:
Congress did not pass civil rights legislation from the 1870s to the late 1950s mainly because those in power were unaware, unconcerned, or strongly opposed. It was a period marked by widespread racial discrimination and segregation, particularly in the Southern states. Many politicians at the time held racist views and were resistant to any measures that would grant equal rights to African Americans.
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