List all former departments that were formerly Cabinet-level in the United States.

Former executive and Cabinet-level departments
Department of War (1789–1947), headed by the secretary of war: renamed Department of the Army by the National Security Act of 1947.
Department of the Navy (1798–1949), headed by the secretary of the Navy: became a military department within the Department of Defense.
Post Office Department (1829–1971), headed by the postmaster general: reorganized as the United States Postal Service, an independent agency.
National Military Establishment (1947–1949), headed by the secretary of Defense: created by the National Security Act of 1947 and recreated as the Department of Defense in 1949.
Department of the Army (1947–1949), headed by the secretary of the Army: became a military department within the Department of Defense.
Department of the Air Force (1947–1949), headed by the secretary of the Air Force: became a military department within the Department of Defense.

The Department of War, the Department of the Navy, the Post Office Department, the National Military Establishment, the Department of the Army, and the Department of the Air Force.