 The first African American to be elected to Congress in Michigan, Diggs made significant contributions to the struggle for civil rights.In April 1955, he gave a well received speech to a crowd of about 10,000 in Mound Bayou, Mississippi, at the annual conference of the Regional Council of Negro Leadership (RCNL), probably the largest civil rights group in the state.His host was the RCNL's leader, Dr. T.R.M.