He became a union official in 1936, and worked for Nye Bevan in the TGWU. He entered Parliament as the member for Belper in the 1945 general election, and became Minister of Works in 1951, but lost this position last year due to the loss at the 1951 general election.
Brown was deputy leader of the party under Hugh Gaitskell, and challenged for the leadership after Gaitskell's death, but was defeated by Harold Wilson. After Labour returned to government in 1964, under Wilson he was made Secretary of State for Economic Affairs and instituted price and wage controls. He became Secretary of State for Foreign Affairs in 1966, but resigned in 1968 after a long period failing to cope with alcoholism.
He lost his seat in the 1970 general election and was created Baron George-Brown. He left the Labour party in 1976, and entered business. He died in 1985.