Navy Secretary Ray Mabus, a former governor of Mississippi, planned to announce the honor during a speech at Jackson State University in Jackson, Miss. The nearly 700-foot-long vessel named for Evers will deliver food, ammunition and parts to other ships at sea.
During the civil rights movement Evers organized nonviolent protests, voter registration drives and boycotts in Mississippi, rising to the post of national field secretary for the National Association for the Advancement of Colored People.
In 1963 Evers was assassinated in the driveway of his home in Jackson after returning from a meeting with NAACP lawyers. His death prompted President John F. Kennedy to ask Congress for a comprehensive civil rights bill.
Evers was born in Decatur, Miss., in 1925 and served in the Army during World War II. He returned to Mississippi, earned a degree from Alcorn College in 1952 and became active in the NAACP and its civil rights work in his home state.
Thirty-seven when he was shot to death by a white supremacist, Evers was buried at Arlington National Cemetery. His killer, Byron De La Beckwith, was not convicted until 1994.
"The selection of Medgar Evers ... honors the pioneering spirit of the late civil rights activist from Mississippi who forever changed the face of race relations in the South," according to an administration statement. "At a time when our country was wrestling with finally ending segregation and racial injustice, Evers led civil rights efforts to secure the right to vote for all African-Americans and to integrate public facilities, schools and restaurants."
The Navy names ships in the support fleet to honor pioneers, explorers and other notables. The Navy ship honoring Evers is the first named for an African-American since President Barack Obama took office.