During the early part of December 1965, the 4th Battalion, 9th Infantry, was in Alaska preparing for its annual winter maneuver to be conducted in January 1966 in temperatures of 50 below zero. In the midst of these low temperatures, some "hot news" kindled the interior of Alaska: The "Manchus" were being assigned to the famed jungle trained "Tropic Lightning" Division in Hawaii.
Eight weeks of arduous jungle training in a tropical enviroment readied the battalion for its deployment to Vietnam.
April 29 saw the battalion disembark the ship General Walker at Vung Tau, Vietnam. Within a few days, the "Manchus" were at Cu Chi to take their place along other elements of the "Tropic Lightning" Division....in combat.
Notable battalion-size operations conducted by the "Manchu" include Asheville, Wahiawa, Joliet I and II, Helemano, and Kahana I and II.
While assigned to the 25th Division, the 4th Battalion received two Presidential Citations and added 12 campaign streamers to the Regimental Colors for Combat Operations in the Republic of South Vietnam. On August 2, 1972 the 4th Battalion was relieved from assignment to the 25th Infantry Division and was reassigned to Alaska with the 172nd Infantry.
In the four years and six months service in Vietnam fellow Manchus carried on the regimental tradition arising from deeds of Valor, Acts of Courage and Moments of Self Sacrifice. The 4th Battalion Manchus suffered many casualties of wounded and those that paid the supreme sacrifice.