From the Summary: "In total, 162 African Americans have served in Congress. This total includes  152 African Americans (146 Representatives and 6 Delegates) elected only to the House of Representatives;  9 African Americans elected or appointed only to the Senate; and  1 African American who has served in both chambers. [...] Most recently, the 116 th Congress began with the highest number of African American Members ever at the start of a Congress: 57 (52 Representatives, 2 Delegates, and 3 Senators). Other information in this report includes the following:  Numbers of African Americans who have served in Congress by party and type of service;  Numbers of African Americans who have served in each Congress since 1870;  Numbers of African Americans who have served in the House and Senate by state, district, or territory;  Means of entry to Congress, including regular elections, special elections, and appointments;  Brief background and selected data on the Congressional Black Caucus (CBC);  Lists of selected 'firsts' for African Americans in Congress;  Lists of the African Americans who have served in leadership;  Records for length of service in the House and Senate; and  Lists of the African American women in the 116 th Congress."
CRS Report for Congress, RL30378
Congressional Research Service: https://crsreports.congress.gov/