President Barack Obama speaks near the Edmund Pettus Bridge, Saturday, March 7, 2015, in Selma, Ala. This weekend marks the 50th anniversary of "Bloody Sunday,' a civil rights march in which protestors were beaten, trampled and tear-gassed by police at the Edmund Pettus Bridge, in Selma.

Credit: AP Photo/Gerald Herbert

Selma civil rights milestone marked by first black president

Under a broiling sun, the first black U.S. president praised the figures of a civil rights era that he was too young to know but that helped…