Byrnes, James Francis (1879–1972), a United States public official. In a political career that spanned a half century, Byrnes held public office on the local and state levels and in all three branches of the federal government. During World War II, as director of war mobilization, he wielded power second only to that of President Franklin D. Roosevelt.

Byrnes was born in Charleston, South Carolina. After admission to the bar in 1903, he practiced law and edited a newspaper. In 1908 he was elected a public prosecutor in South Carolina. He served in the U.S. House of Representatives as a Democrat, 1911–25. In 1930 Byrnes was elected to the U.S. Senate. He became one of its most influential members and was a supporter of the liberal New Deal programs. In 1941 Roosevelt appointed him associate justice of the U.S. Supreme Court. Byrnes resigned in 1942 to direct the Office of Economic Stabilization.

After heading the Office of War Mobilization, 1943–45, Byrnes was named secretary of state by President Truman. In this post, he helped to formulate early Cold War foreign policy. Byrnes resigned in 1947 and joined a private law firm. As governor of South Carolina, 1951–55, he was a conservative on most issues, including school segregation.