Bayard Rustin: Openly gay in a homophobic era, Bayard Rustin was a tireless activist. Although a Pennsylvania native, Rustin, who was also a Quaker, flourished in Harlem, joining the national effort to free the Scottsboro boys as well as contributing to early Communist efforts to end racism. Working with A. Philip Randolph, the legendary labor and civil rights leader, Rustin was part of the original March on Washington, proposed first in 1941 and was the main organizer of the historic 1963 march. Rustin participated in the 1947 Freedom Rides organized by the Fellowship of Reconciliation (FOR) and the Congress of Racial Equality (CORE). Traveling to India in 1948, Rustin, who studied with Gandhi’s disciples and was a critical advisor during the Montgomery Bus Boycott, is credited for fully converting Dr. King to nonviolent direct action.

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Few Americans are unaware of the historic contributions African-Americans like Frederick Douglass, Booker T. Washington, Ida B. Wells, W.E.B. Du Bois, Marcus Garvey, Martin Luther King, Jr., Malcolm X and, of course, Preisdent Barack Obama have made towards bettering the United States.

But these aren’t the only African-Americans who have helped the United States move closer to becoming “a more perfect union.”

So many people have contributed greatly to the ongoing struggle for justice and equality and yet have remained woefully under-appreciated.

These are just some of the unsung heroes.