Black was born in Harlan, Alabama, a rural town in Clay County. After a brief stint in medical school, Black earned his law degree from the University of Alabama in 1906. While practicing law, he was noted for his success in workers' compensation cases.
Black won a seat in the Senate in 1926 and remained for eleven years. While there, he was a staunch supporter of Franklin Roosevelt's New Deal, and was to remain so while acting as a justice on the Supreme Court.
Appointed to the Supreme Court by Roosevelt, he was confirmed by the Senate to replace Justice Willis Van Devanter and was sworn in on August 19, 1937. His opinion of the majority, ruling in favor of four African-Americans who had been coerced by police into murder confessions, in Chambers v. Florida (309 US 227 1940), made clear that his previous connections with the Klan were not to have an effect on his performance in the Court.
During the anti-Communist McCarthy era of the 1950s, Black became known as a defender of First Amendment rights, perhaps most notably in his lone dissent in Dennis v. United States (341 US 494 1951), and would continue in this throughout the rest of his career on the Court.
Carl Sagan said of Black
"When permitted to listen to alternative opinions and engage in substantive debate, people have been known to change their minds. It can happen. For example, Hugo Black, in his youth, was a member of the Ku Klux Klan; he later became a Supreme Court justice and was one of the leaders in the historic Supreme Court decisions, partly based on the 14th Amendment to the Constitution, that affirmed the civil rights of all Americans: It was said that when he was a young man he dressed up in white robes and scared black folks; when he got older, he dressed up in black robes and scared white folks." The Demon-Haunted World p.431 ISBN 0345409469