21st Army Group

21st Army Group
Formation badge
Active	1943–45
Country	United Kingdom
Branch	British Army
Type	Army Group
Size	1,020,581 officers and men (excluding US forces) 9,248 tanks 6,584 artillery pieces 1,600 aircraft (2nd Tactical Air Force)[1]
Part of	Allied Expeditionary Force
Engagements	World War II Western Front Operation Market Garden Battle of the Nijmegen salient
Commanders
Notable commanders	Bernard Paget Bernard Montgomery

The 21st Army Group was a British headquarters formation formed during the Second World War. It controlled two field armies and other supporting units, consisting primarily of the British Second Army and the First Canadian Army. Established in London during July 1943, under the command of Supreme Headquarters Allied Expeditionary Force (SHAEF), it was assigned to Operation Overlord, the Western Allied invasion of Europe, and was an important Allied force in the European Theatre. At various times during its existence, the 21st Army Group had additional British, Canadian, American and Polish field armies or corps attached to it. The 21st Army Group operated in Northern France, Luxembourg, Belgium, the Netherlands and Germany from June 1944 until August 1945, when it was renamed the British Army of the Rhine (BAOR).