The installation acquired an additional 49,578 acres in 1953 and former United States Air Force and Department of Defense landholdings in the 1950s and 1960s. Major army units stationed at one time or another at Fort Hood included the First, Second, and Fourth Armored divisions. In 1954 Fort Hood was the nation's only two-division installation, and the Third Corps was transferred from Camp Roberts, California. In 1990 the installation was the home of the headquarters of the Third Corps under United States Army Forces command. Fort Hood was located in the Fifth United States Army area.
Fort Hood is one of the largest military installations in the world.
The primary mission of Fort Hood is to maintain a state of readiness for combat missions, and the dominant activity is the training of the Third Armored Corps. A significant portion of the combat-ready air and ground forces of the United States Army is stationed at Fort Hood. The combat readiness of the Third Armored Corps distinguishes Fort Hood from many other installations, which do not have the same rapid and massive military response capability. With the end of the Cold War, military cutbacks became common throughout the United States. However, operations Desert Shield and Desert Storm in 1990-91 halted this deactivation, and more than 25,000 troops were sent from Fort Hood to the Middle East.