The following American forces were based at the Co. Down barracks between 1942 and 1944.
|Start Date||End Date||Unit|
|18th May 1942||9th December 1942||13th Armor (Less 1st Battalion) (1st Armored Division)|
|1942||1942||Headquarters and Headquarters Company, and Company C, Tank Destroyer Battalion (1st Armored Division)|
|1942||1942||Service Company, 1st Armored Division|
|11th June 1942||9th December 1942||Maintenance Battalion, 1st Armored Division (Less Company A and Company B)|
|1942||1942||106th Coast Artillery Battalion (Anti-Aircraft)|
|11th October 1943||8th May 1944||3440th Ordnance Medium Automotive Maintenance Company|
|October 1943||Part of 11th Infantry (5th Infantry Division)|
|29th November 1943||4th Jul 1944||Depot O-602|
St. Patrick's Day Shamrocks
On 12th March 1941, Mrs. Allen, wife of the Commanding Officer, upheld the time-honoured tradition of presenting the shamrock to her husband's Battalion of the Royal Irish Fusiliers at Ballykinler, Co. Down.
On 11th March 1942, Gunners and members of the Auxiliary Territorial Service took part in a training exercise at 17th Anti-Aircraft Practise, Ballykinlar, Co. Down. A military plane towed a target 'kite' while Gunners fired Bofors Guns.
United States Army Demonstration
On 25th June 1942, the United States Army demonstrated training exercises including the use of Stuart and Lee Tanks for an audience including King George VI and Queen Elizabeth.
Aircraft Recognition Training
On 17th September 1942, Sergeants from 241st Light Anti-Aircraft Training Regiment instructed American military personnel on how to recognise wartime aircraft before demonstrating the use of Bofors Anti-Aircraft guns at Ballykinler, Co. Down.