Walter Philip Reuther (; September 1, 1907 – May 9, 1970) was an American labor union leader, who made the United Automobile Workers (UAW) a major force not only in the auto industry but also in the Democratic Party and the Congress of Industrial Organizations (CIO) in the mid 20th century. He was a socialist in the early 1930s and worked closely with the Communist Party in the auto industry in the middle and late 1930s. He was a leader in removing communists from the offices in UAW and CIO in the 1940s. By 1949 he had become a leading liberal and supporter of the New Deal coalition, working to strengthen the labor union movement, raise wages, and give union leaders a greater voice in state and national Democratic party politics. During the 1960s he was a major supporter of the civil rights movement.