173 AIRBORNE BRIGADE (SEPARATE) US ARMY 1 RAR BATTLE GROUP BIEN HOA 1965-1966 On May 5, 1965, the Brigade deployed to South Viet Nam as the first US Army ground combat unit in that war. Upon arrival, the 1st Battalion of the Royal Australian Regiment (1 RAR) and a battery from New Zealand (161Royal NZ Artillery) were attached to the Brigade -- making the 173d Airborne the only multi-national combat unit in the war. Initially headquartered in Bien Hoa, the Brigade operated in the four provinces around Saigon. (Xuan Loc, Long Khanh, Phuoc Long & Phuoc Tuy), but (in its roll as a "Fire Brigade") also went to the Central Highlands (Pleiku / Kontum) to fight Viet Cong. The 173d also conducted constant operations against the southern stronghold of the VC Main Force in the legendary Iron Triangle in War Zone D. The brigade was organized as a balanced airborne combat force consisting of two infantry battalions, an artillery battalion, a support battalion, an engineer company, a cavalry troop, an armour company, and a headquarters company. Upon activation, it became the first and only separate airborne brigade in the United States Army. This was the beginning of a long series of "Firsts" for the Brigade. On 5 May 1965, it became the first US Army ground combat unit committed to the war in South Vietnam, where further organizational changes were to take place. Australians attached to the Brigade were: 1st Battalion, of the Royal Australian Regiment (I RAR) and support troops of the 4/19th Prince of Wales Light Horse Regiment (1Troop), 105 Field Battery Royal Australian Artillery, 161 Field Battery Royal New Zealand Artillery, 3 Field Troop Royal Australian Engineers, 161 Reconnaissance Flight, Royal Australian Army Air Corps, 1st Australian Logistical Support Company. The Brigade's two infantry battalions, the First Battalion of the 503' Infantry (1/503`d) and the Second Battalion, of the 503`d Infantry (2/503`) and the attached Australians of 1 RAR constituted the infantrymen available to the Brigade. Their mission was to protect the Bien Hoa Air Base and to close with and destroy or capture the enemy. This was in fact the first operational ground force formed under the ANZUS Defence Treaty. ANZUS was a mutual defence treaty signed in 1951 between Australia, New Zealand and the United States of America. In 1965 the spirit of this treaty appeared as 173d Airborne Brigade (Sep) a tri-national brigade. The only such tri-national fighting force formed during the Vietnam War. On deployment to South Vietnam in 1965, 1 Troop A Squadron, 4th/19th Prince of Wales's Light Horse Regiment was part of the US 173rd Airborne Brigade combat group. Flag, two colours divided vertically, hoist half mid blue, fly half red. Badge of 173rd Airborne Brigade (730 x 490 mm) in centreflag, 173rd airborne, south vietnam