As the 50th anniversary of the March on Washington nears, efforts led by organizer Bayard Rustin continue to influence contemporary movements, says John D'Emilio, professor of gender and women's studies and history at the University of Illinois at Chicago. An adviser to Martin Luther King Jr., Rustin was a key figure from the American civil rights movement, as well as movements for peace and social justice in post-World War II America.

"Rustin was one of the most important social justice activists in the U.S. in the 20th century," says D'Emilio, author of the acclaimed biography, "Lost Prophet: The Life and Times of Bayard Rustin."

"He was more responsible than anyone for making Gandhi's philosophy a central feature of the civil rights movement."

D'Emilio says many modern movements concerned with war, incarceration, voter registration laws, and economic justice are based on core principles, such as nonviolence, that Rustin practiced when addressing similar concerns.

Despite his significant work, however, Rustin, who was openly gay and briefly involved with Communism, is considered an overlooked advocate for human rights and economic justice.

"Rustin had to figure out how to be an agitator for justice and work effectively without people noticing him, because he was a gay man living in an era when the constraints on that were so intense," D'Emilio explains.

His present-day importance has been underscored by the recent White House announcement that President Barack Obama would posthumously award Rustin the Presidential Medal of Freedom.

D'Emilio is available to comment on the Rustin's life, career, and role in the 1963 March on Washington.