As the Army's first airmobile division, the 1st Cav arrived in Vietnam on Sept. 14, 1965. Less than two months later, demonstrating a mastery of terrain and enemy, it won a Presidential Unit Citation by routing heavy North Vietnamese concentrations around the Ia Drang Valley west of Pleiku. In the next 13 months, Skytroopers met and defeated strong enemy forces throughout the II Corps Tactical Zone.

In January 1968, the Cav was needed in I Corps, arriving in time to blunt the enemy's Tet Offensive. After a bitter battle near Hue in February, the unit moved swiftly in April to relieve the embattled Marine base at Khe Sanh.

In October 1968, the Cav was needed in III Corps to thwart a potential Communist threat. The equivalent of a medium-sized U.S. town took wings and landed at the other end of the Republic of Vietnam. While thrusting against enemy positions along the Cambodian border northwest of Saigon, Some elements of the division moved further south into IV Corps, working with Naval forces in an operation called "Nav-Cav." Thus the 1st Cavalry Division (Airmobile) became the first American division to have fought in all four tactical zones in the Republic of Vietnam.