was the largest amphibious operation to date in the Pacific theater. Their contributions led to a victory that would prove to be decisive in the battle for the Philippines. On 9 January 1945, the 2nd Brigade then participated in the invasion of Luzon, the largest of the Philippines Islands. The brigade was the first into Manila, liberating the Philippine Capital and freeing over 4000 civilians from enemy prison camps. The conquest of Leyte and Luzon were vital to operations in the Pacific, as they denied critical resources to the enemy and provided a staging area from which assaults in the Japanese home islands could be launched. The brigade left Luzon in August 1945 for occupation duty in Japan, becoming the first Allied unit to enter the city of Tokyo. The brigade was inactivated on 25 March 1949 and relieved from assignment to the 1st Cavalry Division. German occupation On 20 May 1949 it was converted and redesignated as the 2nd Constabulary Brigade. The brigade served in Germany until it was inactivated on 15 December 1951. Korea On 1 September 1963 the brigade was reactivated again in Korea as the Headquarters and Headquarters Company, 2nd Brigade, 1st Cavalry Division. The brigade remained at Camp Howze in Korea until 1 July 1965, when the division colors were transferred to Fort Benning, Georgia. Vietnam The division was reorganized and activated as the 1st Cavalry Division (Airmobile), the Army's first Air Assault division. Secretary of Defense Robert S. McNamara shocked many observers when he announced that this new air assault division would be combat ready in only eight weeks. The 1st Cavalry Division (Airmobile) exceeded that demanding goal by reaching REDCON-1 status on 28 July 1965 and deploying to Vietnam in mid-August, only six weeks after the division's organization. The men of 2nd Brigade boarded the USNS General Simon B. Buckner on 16 August 1965, en route to Vietnam. On 14 September 1965, the 2nd Brigade disembarked the USNS Buckner and landed at Qui Nhơn. The brigade, consisting of 1/5 Cavalry, 2nd Battalion, 5th Cavalry Regiment and 2nd Battalion, 12th Cavalry Regiment, loaded into helicopters and flew in-land to the division base camp at Camp Radcliff, An Khê District. The 2nd Brigade became the first brigade in the division to see combat when on 18 September 1965 the 2/12 Cavalry was OPCONed to 101st Airborne Division to participate in Operation Gibralter. The 2nd Brigade