1964 in the Vietnam War

January
On January 30, 1964, a successful coup led by General Nguyen Khanh ousted the military junta led by General Duong Van Minh from the leadership of South Vietnam. It came less than three months after Minh's junta had themselves come to power in a bloody coup against then President Ngo Dinh Diem. The coup was bloodless and took less than a few hours.
 * January 30

February
The Battle of Long Dinh was a battle of the Vietnam War that involved the People's Liberation Armed Forces (Viet Cong) and the Army of the Republic of Vietnam (ARVN).
 * February 26

April
Operation Quyet Thang 202 was a 1964 Army of the Republic of Vietnam operation carried out with US support. The one month-long operation ended with heavy damages to the People's Liberation Armed Forces's (Viet Cong) communication line that linked Do Xa with other National Liberation Front controlled provinces.
 * April 27-May 27, 1964

June
United Nations Security Council Resolution 189, adopted unanimously on June 4, 1964, deplored an incident cased by the penetration of units of the Republic of Vietnam into Cambodia and requested compensation for the Cambodians. The resolution then requested that all States and authorities recognize and respect Cambodia's neutrality and territorial integrity, deciding to send 3 of its members to the places the most recent incidents had occurred to report back to the Council in 45 days with suggestions.
 * June 4

July
The Battle of Nam Dong was fought on July 6, 1964, when the Viet Cong attacked the Nam Dong Civilian Irregular Defense Group (CIDG) camp in an attempt to overrun it.
 * July 6

The first Australian, Warrant Officer Kevin Conway, died in the Vietnam war. Conway was a member of the Australian Army Training Team (Vietnam) AATTV.
 * July 6

August
The Gulf of Tonkin Incident is the name given to two separate incidents involving the Democratic Republic of Vietnam (North Vietnam) and the United States in the waters of the Gulf of Tonkin. On August 2, 1964 the US destroyer USS Maddox while performing a DeSoto mission, was engaged by three North Vietnamese Navy torpedo boats of the 135th Torpedo Squadron, a sea battle, in which the Maddox expended over 280 3" and 5" shells, and which involved the strafing from four USN F8 Crusader jet fighter bombers, all of which resulted in the damage to one US aircraft, one 14.5mm hit on the destroyer, 3 damaged torpedo boats, and 4 North Vietnamese sailors killed and 6 wounded; with no US casualties.
 * August 2 and August 4

The second Tonkin Gulf incident, which occurred on August 4, 1964, was also a naval battle, but this time, may have involved the "Tonkin Ghosts", and no actual NVN Torpedo Boat attacks. The outcome of this second incident was the passage by Congress of the Gulf of Tonkin Resolution, which granted President Lyndon B. Johnson the authority to assist any Southeast Asian country whose government was considered to be jeopardized by "communist aggression". The resolution served as Johnson's legal justification for deploying US conventional forces and the commencement of open warfare against North Vietnam.

Operation Pierce Arrow was a U.S. military operation in response to the Gulf of Tonkin Incident when the USS Maddox of the United States Navy was attacked, sustaining light damage as it gathered electronic intelligence while in the international waters of the Gulf of Tonkin.
 * August 5

October
Nguyễn Văn Trỗi was executed on October 15, 1964. A Vietnamese electrical worker and Viet Cong (National Liberation Front) urban guerrilla. He became known after being captured by the South Vietnamese when trying to assassinate United States Secretary of Defense Robert McNamara and future ambassador Henry Cabot Lodge, Jr. who were visiting South Vietnam in May 1963.
 * October 15, 1964

December
The Battle of An Lao occurred after the Viet Cong captured the district headquarters of An Lao, Binh Dinh, about 300 miles from Saigon. The Viet Cong were successful in repeatedly beating back large numbers of counterattacking ARVN troops.
 * December 7 – December 9

Operation Barrel Roll was a covert U.S. Air Force 2nd Air Division (later the Seventh Air Force) and U.S. Navy Task Force 77, interdiction and close air support campaign conducted in the Kingdom of Laos between 14 December 1964 and 29 March 1973 concurrent with the Vietnam War.
 * 14 December 1964 - 29 March 1973

The Brinks Hotel in Saigon was bombed by the Vietcong on the evening of December 24, 1964, during the Vietnam War. Two Vietcong operatives detonated a car bomb underneath the hotel, which housed United States Army officers; the explosion killed two American officers and injured approximately 60, including military personnel and Vietnamese civilians.
 * December 24

The Battle of Binh Gia, a Catholic village not far from Saigon; is attacked by the VC. Both sides proclaim victory.
 * 28 December - 1 January 1965