President Harry Truman played a significant role in advancing civil rights for African Americans during his presidency. In 1948, Truman issued Executive Order 9981, which desegregated the military and mandated equal treatment and opportunity for all service members regardless of race. This was a groundbreaking move towards ending segregation within the armed forces.

Truman also established the President's Committee on Civil Rights, which produced a report titled "To Secure These Rights" in 1947. The report called for an end to segregation in the military, federal government, and federally-funded programs, as well as for the protection of voting rights for African Americans.

Additionally, Truman supported the integration of Major League Baseball when he publicly endorsed and encouraged the Brooklyn Dodgers to sign Jackie Robinson, breaking the color barrier in professional baseball in 1947.

Overall, President Harry Truman's actions and initiatives in support of civil rights and desegregation were significant contributions to Black history and the ongoing struggle for racial equality in the United States.