The Fifth Division of the Army of the Republic of Vietnam (ARVN)—the army of the nation state of South Vietnam that existed from 1955 to 1975—was part of the III Corps that oversaw the region of the country surrounding the capital, Saigon.
The Fifth Division was based in Bien Hoa, a town on the northern outskirts of Saigon, and due to the division's close proximity to the capital Saigon was a key factor in the success or failure of the various coup attempts in the nation's history. As a result, the loyalty of the commanding officer of the division was crucial in maintaining power.
In the 1960 South Vietnamese coup attempt, the loyalist Colonel Nguyen Van Thieu used the Fifth Division to storm into Saigon to save President Ngo Dinh Diem.
However, in the successful coup attempt of 1963, Thieu rebelled and his division along with the rest of the III Corps of Ton That Dinh, attacked Saigon. Thieu himself led the successful siege on Gia Long Palace. As a result, the leading generals made Thieu a general.
The principal sub-units of the division were the 7th, 8th and 9th Infantry Regiments and the 1st Armored Cavalry Regiment. The 9th Infantry Regiment (Devine Elephant) was based at Quan Loi near An Loc. The 1st ACR was based at the division's forward base camp at Lai Khe.