Final answer:
Robert C. Weaver was the first African American cabinet member, serving as Secretary of Housing and Urban Development under President Lyndon Johnson.
Step-by-step explanation:
The first African American cabinet member was Robert C. Weaver. Weaver became the nation's first Black cabinet secretary in 1966, serving as President Lyndon Johnson's Secretary of Housing and Urban Development. He was a member of Roosevelt's unofficial advisory group called the 'Black Cabinet'.