2-321 FAR traces its lineage to Battery B, 321st Field Artillery, which organized on 2 September 1917 at Camp Gordon, Georgia.

After training at Camp Gordon until May 1918, the battery shipped to France, and participated with the regiment in the St. Mihiel, Meuse Argonne and Lorraine 1918 campaigns.

Following the Armistice, the battery redeployed to the United States and was demobilized at Camp Dix, New Jersey in May 1919.

At the time of notification, the battalion was at 50% strength, but received 211 "fillers" from within the 82d Division Artillery over the 16 hours following the deployment notification and deployed at 100% strength of 458 personnel (39 officers, 2 warrant officers and 416 enlisted personnel).

Battery A deployed with Task Force (TF) Privette (2d Battalion, 505th Parachute Infantry Regiment [2-505 PIR]), arriving at Chu Lai between 16 and 19 February 1968.

Each serial stopped at Da Nang overnight and arrived at Hue/Phu Bai on 4, 5 and 7 March 1968 without enemy contact.

Upon arrival in Hue/Phu Bai, the brigade began development of Camp Rodriguez at map coordinates YD817147.

On 28 March 1968, Battery C received 20 rounds of 122mm rockets, wounding one man and damaging two ¼-ton trucks.

On 30 March 1968, Battery B received 8 rounds of 82mm mortar, wounding three men and damaging the mess tent.

On 3 April, Battery C moved by road to FSB Geronimo in order to support 1-508 PIR in Area of Operations (AO) Bass.

Throughout the quarter, the battalion fired 66,525 rounds during 7,225 missions, and was credited with 16 enemy killed by artillery.

[5] Following redeployment from Vietnam, 2-321 continued to serve as a direct support battalion in the 82nd Airborne Division Artillery.

In 1986, the battalion was inactivated and reflagged as 3-319 AFAR in conjunction with the implementation of the U.S. Army Regimental System.

As part of the transformation of the Army into modular brigade combat teams, 2-321 was reactivated as the 4th BCT, 82nd ABN's organic field artillery battalion.

Note: The published US Army lineage lists no War on Terrorism campaigns, as of 17 August 2006.