Fort Polk was established in 1941 and named for the Right Reverend Leonidas Polk, first Episcopal Bishop of the Diocese of Louisiana and a Confederate General. The fort trained thousands of soldiers for World War II in what was called the Louisiana Maneuvers. Facing potential mobilization overseas, the Maneuvers were designed to test troops and practice their modernization and mechanization. The extensive practice led to the creation of 16 armored divisions after the war.


Though Polk closed after training soldiers for the Korean War, it was reactivated during the Berlin Crisis of 1961. In 1962 it became an infantry training center and provided advanced training for Vietnam-style combat.


In 1974, the 5th Infantry Division became a major tenant at Polk, until it relocated in 1993. On March 12, 1993, Polk became the official home of the Joint Readiness Training Center (JRTC), one of the Army's three "Dirt" Combat Training Centers which provides training of infantry brigade task forces and their subordinate elements in the Joint Contemporary Operational Environment. The JRTC is focused on highly realistic training for more efficient unit readiness and often integrates other Armed Services and civilian role players for practice dealing with realistic situations with realistic environments, civilians, housing and neighborhoods, and threats and nonthreats.


In 2005, Polk saw the activation of the 4th Brigade, 10th Mountain Division. This new modular brigade is part of Army restructuring from division-based to brigade-based modules to act as more self-sufficient and stand-alone units.