How did the April 1866 Civil Rights Act contradicted the Supreme Court's 1857 Dred Scott decision?

Civil Rights Act of 1866

First United States federal law to define citizenship and affirm that all citizens are equally protected by the law (especially African-Americans)

The Civil Rights Act of 1866 (14 Stat. 27–30, enacted April 9, 1866, but not ratified until 1870) was the first United States federal law to define citizenship and affirm that all citizens are equally protected by the law. It was mainly intended, in the wake of the American Civil War, to protect the civil rights of persons of African descent born in or brought to the United States.

Explanation:

the answer to your question is,

old stone age.

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