1965 in the Vietnam War

February
The Viet Cong attack on Pleiku airbase (aka Camp Holloway Airfield) occurred on the night of February 6, 1965. The attack left eight Americans dead and 128 wounded, and it prompted the United States to launch Operation Flaming Dart against North Vietnam in retaliation. The Vung Ro Bay Incident refers to the discovery of a 100-ton North Vietnamese naval trawler unloading munitions on a beach in South Vietnam's Vung Ro Bay on 16 February 1965. The incident spurred further U.S. Navy involvement in the Vietnam War.
 * February 6
 * February 16

March
Operation Rolling Thunder, the largest U.S bombing raid against North Vietnam, commences as 100 U.S. fighter-bombers bomb all across targets in North Vietnam. The operation is meant to last eight weeks, but instead lasts three years.
 * March 2, 1965 - November 2, 1968

American units also bomb the Ho Chi Minh Trail, a valuable supply route that ran throughout North and South Vietnam and supported communist forces. The trail is routinely bombed throughout the war with little success as it is consistently rebuilt by North Vietnamese forces. The first American combat troops arrive in Vietnam as 3500 U.S. Marines land at China Beach to defend the American airbase at Da Nang. They join the already 23,000 American advisors and this starts principal U.S. involvement in the Vietnam War. Viet Cong troops storm into the U.S. Embassy in Saigon and bomb the area, wounding several Americans.
 * March 5
 * March 30

April
President Johnson authorizes sending two more U.S. Marine battalions and 20,000 logistics personnel to Vietnam.
 * April 1

May
Australian Defence Force are first deployed to Bien Hoa, north-east of Saigon, South Vietnam. The first U.S. Army troops from the 173rd Airborne Brigade arrive in Vietnam. The Battle of Song Be was a major action between the National Front for the Liberation of South Vietnam (Viet Cong) and Army of the Republic of Vietnam (ARVN) in May 1965. The Battle of Ba Gia or Bãi Xoan was a battle of the Vietnam War, that began after an ARVN battalion was ambushed by Viet Cong (VC) forces on May 28, 1965. The battle highlighted the vulnerability of the ARVN as a military force against the flexible VC.
 * May 3
 * May 10-May 15
 * May 28 - June 1

June
The Battle of Đồng Xoài was waged by the National Liberation Front, otherwise known as the Viet Cong, during the Communist winter-spring offensive of 1965. It was the largest battle during that stage of the Vietnam War.
 * June 10–11

July
Communist China begins to send troops to help defend the northern reaches of North Vietnam.

The USSR also starts to send men to Vietnam.

Members of the New Zealand armed forces are deployed to South Vietnam.
 * July 21

August
Operation Starlite was the first offensive military action conducted by a purely U.S. military unit during the Vietnam War. The operation was launched based on intelligence provided by Major General Nguyen Chanh Thi, the commander of the South Vietnamese forces in northern I Corps area. Lieutenant General Lewis W. Walt devised a plan to launch a pre-emptive strike against the Viet Cong regiment to nullify the threat on the Chu Lai base.
 * August 17 - August 24

October
The Siege of Plei Me was a battle during the Vietnam War, which led up to the Battle of Ia Drang.
 * October 19 - October 25

November
Operation Hump was a search and destroy operation by the 173rd Airborne Brigade, in an area about 17.5 miles north of Bien Hoa. The 1st Battalion, Royal Australian Regiment, deployed south of the Dong Nai River while the 1st Battalion, 503rd Infantry, conducted a helicopter assault on an LZ northwest of the Dong Nai and Song Be Rivers. The Battle of Gang Toi was fought on 8 November 1965 between Australian troops and the Viet Cong, during the Vietnam War. The battle was one of the first engagements between the two forces during the war and occurred when the 1st Battalion, Royal Australian Regiment (1RAR) struck a Viet Cong bunker system in the Gang Toi Hills, in northern Bien Hoa Province. The Battle of Ia Drang was one of the first major battles between the United States Army and the People's Army of Vietnam (PAVN) referred to by US fighting units as the North Vietnamese Army (NVA) during the Vietnam War.
 * November 5 - November 8
 * November 8
 * November 14–18

December
Operation Game Warden Task force 116, was an operation to deny Viet Cong access to the resources in the Mekong Delta which was conceived of in December 1965.
 * December 18