Alexander Meigs Haig Jr. (December 2, 1924 – February 20, 2010) was an American politician who served as the 59th United States Secretary of State under President Ronald Reagan and previously as 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 position, 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.

Haig was born and raised in Pennsylvania. He graduated from the U.S. Military Academy and served in the Korean War, during which he served as an aide to general Alonzo Patrick Fox and general Edward Almond. Afterward, he served as an aide to defense secretary Robert McNamara. During the Vietnam War, Haig commanded a battalion and later a brigade of the 1st Infantry Division. For his service, Haig received the Distinguished Service Cross, the Silver Star with oak leaf cluster, and the Purple Heart.