Fort Campbell opened in early 1942, and was immediately put to use training three armored and one infantry division, in support of the war effort in Europe and the Pacific. After World War II, Fort Campbell continued to grow, and in 1956 the 101st Airborne Division was reactivated, with Fort Campbell as their home. Other tenant units at Fort Campbell include the 5th Special Forces Group, the 160th Special Operations Aviation Regiment (SOAR), and the 57th Explosive Ordance Disposal Group.

First established in 1853, Fort Riley was primarily founded as protection for mail trains as well as travel routes out west. World War I caused a great expansion in the size of Fort Riley, as did World War II. During the Korean War and Vietnam many different infantry units were trained at Fort Riley, including the famous 1st Infantry Division (The Big Red One).

Today, the primary unit stationed at Fort Riley is still the 1st Infantry Division.

Established in 1908 in order to defend the islands of Hawaii, Schofield Barracks is the home of the 25th Infantry Division (known as "Tropic Thunder"), the 8th Theater Sustainment Command, and also the command headquarters of US Army Hawaii (USARHAW). It features over 17,000 acres of ranges and training area.

Officially known as Joint Base Lewis-McChord (combining the Army's Fort Lewis and the Air Force's McChord AFB) the original Army installation was founded in 1917. Joint Base Lewis-McChord (JBLM) tenant units for the US Army include the US Army I Corps, including numerous infantry, medical, engineer, and support personnel. JBLM contains more than 86,000 acres with more than 25,000 soliders and civilians working on base.

Established in 1861, Fort Myer was originally used as a training camp for the US Army Signal Corps, and in 1908, saw the first flight of an aircraft at a military base. During World War I was used as a staging area for engineer, chemical, and artillery soldiers. During World War II, Fort Myer was again used as a staging area for a large number of soldiers, including General Patton, who was stationed at Fort Myer for a time.

Fort Myer was joined with the US Marines Henderson Hall to make Joint Base Myer-Henderson by the 2005 Base Realignment and Closure Commission to increase the efficiency of the two military installations. Tenant units at Fort Myer include the 3rd Army (The Old Guard), which includes the sentries guarding the Tomb of the Unknown Soldier, as well as the US Army's Band "Pershing's Own", Arlington National Cemetery Honor Guard Teams, as well as numerous other units.

Originally founded as a local municipal airport, the Army built a base at the field in 1940, and was used to train both bomber and anti-submarine aircrews during World War II. From 1949-1967 the airfield was known as Hunter Air Force Base, and was used by the Strategic Air Command until the Army took over in 1967.

Today Hunter Army Airfield is part of Fort Stewart, and as such primarily houses the aviation units of the 3rd Infantry Division. Hunter Army Airfield also allows the 3rd Infantry Division to quickly and efficiently deploy units worldwide

Established in 1941, Fort Stewart was established as a 5,000 acre installation for the training of anti-aircraft artillery gunners. Eventually Fort Stewart would encompass over 280,000 acres - needed space for the live-fire training of the anti-aircraft weapons. During the Korean War Fort Stewart was again used in the training of anti-aircraft weapons, however during the War in Vietnam elements from the US Army Aviation School began to use Fort Stewart for rotary-wing training.

Today, in addition to continuing to support Army Aviation, Fort Stewart is the home to the 3rd Infantry Division.

Established in 1885, Fort McPherson was used as a recruitment center and general hospital during the Spanish-American War. It filled the same functions during World War I, also being used to house POW's and train officers. Because of the large buildup of forces during World War II, Fort McPherson was used as a reception and separation center for soldiers entering and leaving the military, and again as a major medical center.

Until it was listed for closure in the 2005 Base Realignment and Closing report, and closed in 2011, Fort McPherson was used by the US Army Forces Command, Reserve Command, as well as a Military Entrance Processing Station (MEPS). All of these units will be moved to other, active Army Installations.

Established in 1941, Fort Gillem primary mission is supporting nearby Fort McPherson. However, the 2005 Base Realignment and Closure (BRAC) has recommended that both bases be shut down. It is unclear if one or both bases may be saved, but Fort Gillem will likely not be totally shut down, due to the hazardous materials permanently stored underground on the base.

Established in 1791, Fort McNair was intended from the beginning to be a major defense site for the US capitol. However, the site proved ineffective against the British when they assaulted the capitol during the War of 1812. During the late 19th and early 20th centuries the base housed a predecessor to the Walter Reed Medical Center, and in 1904 the Army War College was established at Fort McNair. In 1924 the Army Industrial College was founded at Fort McNair, and in 1976 these two schools merged to form the National Defense University.