Operation Chicago Peak was a joint

U.S. Army The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United Stat ...

and

Army of the Republic of Vietnam The Army of the Republic of Vietnam (ARVN; ; ) composed the ground forces of the Republic of Vietnam Military Forces, South Vietnamese military from its inception in 1955 to the Fall of Saigon on 30 April 1975. Its predecessor was the ground forc ...

(ARVN) military operation during the

Vietnam War The Vietnam War (1 November 1955 – 30 April 1975) was an armed conflict in Vietnam, Laos, and Cambodia fought between North Vietnam (Democratic Republic of Vietnam) and South Vietnam (Republic of Vietnam) and their allies. North Vietnam w ...

designed to keep pressure on the

People's Army of Vietnam The People's Army of Vietnam (PAVN), officially the Vietnam People's Army (VPA; , , ), also recognized as the Vietnamese Army (), the People's Army () or colloquially the Troops ( ), is the national Military, military force of the Vietnam, S ...

(PAVN) units in the

A Sầu Valley The A Shau Valley (Vietnamese: ''thung lũng A Sầu'') is a valley in Vietnam's Huế, along the border of Laos. The valley runs north and south for 40 kilometers and is a 1.5-kilometer-wide flat bottomland covered with tall elephant grass, fla ...

and prevent them from mounting any attacks on the neighboring coastal provinces.

Background

The A Sầu Valley was an important corridor for the PAVN and

Viet Cong The Viet Cong (VC) was an epithet and umbrella term to refer to the communist-driven armed movement and united front organization in South Vietnam. It was formally organized as and led by the National Liberation Front of South Vietnam, and ...

(VC), who used it to transport supplies from

Laos Laos, officially the Lao People's Democratic Republic (LPDR), is the only landlocked country in Southeast Asia. It is bordered by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the southeast, and Thailand to the west and ...

into

South Vietnam South Vietnam, officially the Republic of Vietnam (RVN; , VNCH), was a country in Southeast Asia that existed from 1955 to 1975. It first garnered Diplomatic recognition, international recognition in 1949 as the State of Vietnam within the ...

as well as a staging area for attacks. Previous sweeps of the valley in

Operation Delaware Operation Delaware/Operation Lam Son 216 was a joint military operation launched during the Vietnam War. It began on 19 April 1968, with troops from the United States and the Army of the Republic of Vietnam (ARVN) moving into the A Sầu Valley ...

(19 April – 17 May 1968),

Operation Dewey Canyon Operation Dewey Canyon was the last major offensive by the 3rd Marine Division during the Vietnam War. It took place from 22 January through 18 March 1969 and involved a sweep of the People's Army of Vietnam (PAVN)–dominated A Shau and Song ...

(22 January – 18 March 1969), Operation Massachusetts Striker (28 February - 8 May 1969) and

Operation Apache Snow Operation Apache Snow was a joint U.S. Army and Army of the Republic of Vietnam (ARVN) military operation (10 May – 7 June 1969) during the Vietnam War designed to keep pressure on the People's Army of Vietnam (PAVN) units in the A Sầu Vall ...

(10 May - 7 June 1969) in the preceding years had temporarily disrupted PAVN operations, but were unsuccessful at removing the PAVN/VC from the valley. The operation was scheduled to commence with the end of the monsoon and U.S. forces launched

Operation Texas Star Operation Texas Star was a military operation of the Vietnam War that took place in Quảng Trị and Thừa Thiên Provinces from 1 April to 5 September 1970. Operation This was a follow-on operation to Operation Randolph Glen. The main ob ...

on 1 April to establish firebases to support the operation. However the

Battle of Fire Support Base Ripcord The Battle of Fire Support Base Ripcord was a 23-day battle between elements of the U.S. Army 101st Airborne Division and two reinforced divisions of the People's Army of Vietnam (PAVN) that took place from 1 to 23 July 1970. It was the last ma ...

and the engagement of PAVN forces on the

Khe Sanh Khe Sanh () is the district capital of Hướng Hoá District, Quảng Trị Province, Vietnam, located 63 km west of Đông Hà. During the Vietnam War The Vietnam War (1 November 1955 – 30 April 1975) was an armed conflict ...

plateau in Operation Clinch Valley forced the postponement and scaling back of the operation. One of the objectives of the operation, the Co Pung Mountain area, 4 km northeast of the A Sầu was found to be heavily defended by PAVN with 11 helicopters damaged by anti-aircraft fire and the acting commander of the

101st Airborne Division The 101st Airborne Division (Air Assault) ("Screaming Eagles") is a light infantry division (military), division of the United States Army that specializes in air assault military operation, operations. The 101st is designed to plan, coordinat ...

, Brigadier general Sidney Bryan Berry, was instructed to avoid heavy U.S. casualties.

Operation

The scaled-back operation was finally launched on 25 July with the 2nd Battalion,

502nd Infantry Regiment The 502nd Infantry Regiment (502nd IR), previously titled the 502nd Parachute Infantry Regiment (502nd PIR), is an infantry regiment of the United States Army. The regiment was established shortly after U.S. entry into World War II, and was as ...

landed to reopen Firebase Maureen east of Co Pung Mountain. On 30 July with artillery support from Firebase Maureen, the ARVN 3rd Regiment, 1st Infantry Division was landed on Co Pung Mountain. After some initial fighting, the PAVN withdrew from the mountain. On 6 August the PAVN 6th Regiment attacked the ARVN 1st Regiment's Firebase O'Reilly 8 km north of Ripcord. 1st Division commander General

Ngô Quang Trưởng Ngô Quang Trưởng (13 December 1929 — 22 January 2007) was an officer in the Army of the Republic of Vietnam (ARVN). Trưởng gained his commission in the Vietnamese National Army in 1954 and moved up the ranks over the next decade, most ...

reinforced O'Reilly with another Regiment and the ARVN defended the base for two months before abandoning it in early October. On 12 August, 101st Airborne commander Major general John J. Hennessey terminated the operation to allow the ARVN to concentrate on defending Firebase O’Reilly. It was speculated that the PAVN attacks around O'Reilly were to divert allied attention from the logistical activity along the border and in Laos or the PAVN were attempting to draw allied forces out of the populated lowlands to provide greater freedom of movement for VC forces in a continuing assault on the

pacification Pacification may refer to: The restoration of peace through a declaration or peace treaty: *Pacification of Ghent, an alliance of several provinces of the Netherlands signed on November 8, 1576 *Treaty of Berwick (1639), or ''Pacification of Berwi ...

and

Vietnamization Vietnamization was a failed foreign policy of the Richard Nixon administration to end U.S. involvement in the Vietnam War through a program to "expand, equip, and train South Vietnamese forces and assign to them an ever-increasing combat role, a ...

programs.

Aftermath

PAVN losses were 97 killed and ARVN losses were three killed, there were no U.S. killed.

References

{{DEFAULTSORT:ChicagoPeak, Operation Battles of the Vietnam War involving the United States Battles and operations of the Vietnam War in 1970 History of Huế