Hiram Rhodes Revels was sworn in as the first African American U.S. Senator on February 25, 1870. He had been in politics only two years, first serving as a Natchez alderman and then as the Adams County representative to the Mississippi State Senate. The State Senate elected him to the U.S. Senate on the strength of his oratory in the prayer he gave at its opening session. (U.S. Senators were not elected by popular vote until the ratification of the 19th Amendment in 1913.)
Two months before the end of his term, he resigned his seat to become president what is now Alcorn State University. He also resumed his career as a minister, which he had begun on 1857 by pastoring African Methodist Episcopal churches throughout the Midwest and serving as a chaplain during the Civil War. During this time he switched from the AME church to the MEC. He later left Alcorn State to teach at MEC-affiliated Rust College, to edit the Christian Advocate denominational newspaper, and to serve as Presiding Elder of the Upper Mississippi District. He died while attending a church conference in Aberdeen, Mississippi.
Read more here http://history.house.gov/…/R/REVELS,-Hiram-Rhodes-(R000166)/