Harry Flood Byrd Sr. (June 10, 1887 – October 20, 1966) was an American newspaper publisher, politician, and leader of the Democratic Party in Virginia for four decades as head of a political faction that became known as the Byrd Organization. Byrd served as Virginia's governor from 1926 until 1930, then represented it as a United States Senator from 1933 until 1965. He came to lead the "conservative coalition" in the United States Senate, and opposed President Franklin D. Roosevelt, largely blocking most liberal legislation after 1937. His son Harry Jr. succeeded him as U.S. Senator, but ran as an Independent following the decline of the Byrd Organization.