Alexander Meigs Haig Jr. was an American politician, diplomat, and military officer who served as the 59th United States Secretary of State under President Ronald Reagan and previously as the 5th White House chief of staff under Presidents Richard Nixon and Gerald Ford, as well as United States Deputy National Security Advisor under President Nixon. A member of the Republican Party, he was a general in the U.S. Army prior to and in between these cabinet-level positions, serving first as the vice chief of staff of the Army and then as Supreme Allied Commander Europe. In 1973, Haig became the youngest four-star general in the U.S. Army's history.