Quảng Tín was a province of South Vietnam

South Vietnam

South Vietnam was a state which governed southern Vietnam until 1975. It received international recognition in 1950 as the "State of Vietnam" and later as the "Republic of Vietnam" . Its capital was Saigon...

. It was created from the part of Quang Nam province

Quang Nam Province

Quảng Nam is a province on the South Central Coast of Vietnam. It is bordered by Thua Thien-Huế province to the north, the nation of Laos to the west, Kon Tum Province to the southwest, Quảng Ngãi Province to the southeast, the South China Sea to the east, and the city of Da Nang to the...

 on the south side of the Que Son Valley

Que Son Valley

is a district in Quang Nam province, Vietnam. During the Vietnam War, it was the site of heavy fighting, including Operation Union I & II. From 1962 to 1967, the southern side of the valley was Quang Tin province....

 on July 31, 1962. The capital was Tam Ky. During the Vietnam War

Vietnam War

The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

 it was the site of heavy fighting, including Operation Union

Operation Union

Operation Union was a military operation conducted by the United States Marine Corps during the Vietnam War. It was a search and destroy mission in the Que Son Valley carried out by the 1st Marine Regiment. The object of the operation was the 2nd Division of the People’s Army of Vietnam...

 I & II

Operation Union II

Operation Union II was a military operation that took place in the Vietnam War. It was a search and destroy mission in the Que Son Valley carried out by the 5th Marine Regiment. Launched on May 26, 1967 the operation ended June 5. The North Vietnamese Army lost 701 killed and 23 captured, while U.S...

. The province was merged back into Quang Nam following the unification of the Socialist Republic of Vietnam on July 2, 1976.