On February 25, 1870 Hiram Rhodes Revels became the first black member of the United States Congress. At the time, as in every state, the Mississippi legislature elected U.S. senators; they were not elected by popular vote until after ratification of the 17th Amendment in 1913.
When Revels arrived in Washington, D.C., Southern Democrats opposed seating him in the Senate. For the two days of debate, the Senate galleries were packed with spectators at this historic event. The Democrats based their opposition on the 1857 Dred Scott Decision which ruled that people of African ancestry were not and could not be citizens.
Supporters of Revels made arguments ranging from relatively narrow and technical issues to the fundamental arguments about the meaning of the Civil War.
During his tenure, Revels advocated compromise and moderation. He vigorously supported racial equality and worked to reassure his fellow senators about the capability of African Americans.
Summarized from Wikipedia.
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