Army Group Royal Artillery

An Army Group Royal Artillery (AGRA) was a British Commonwealth military formation type during the Second World War and shortly thereafter, generally assigned to Army corps. An AGRA was mainly composed of medium artillery regiments but heavy regiments and field regiments were also used. They were moved at need from corps to corps within an army.

World War I had been arguably the first 'artillery war', in which Britain's Royal Artillery (RA) advanced enormously, both technologically and tactically. The previously independent Heavy and Siege batteries of the Royal Garrison Artillery (RGA) were grouped into Heavy Artillery Groups, later termed 'brigades' (a lieutenant-colonel's command), at the disposal of Army Corps. But despite heated arguments, no higher organisational command structure was evolved.

By the time World War II broke out, the RGA had been integrated into RA and the 'brigades' of 'heavy' and 'siege' guns had become 'regiments of 'medium' and 'heavy' artillery with more modern equipment. But they still lacked a higher command structure for flexibility and concentration in the control of artillery above the divisional level, the need for which became apparent to the British Expeditionary Force during the Battle of France in 1940 and the early part of the Western Desert Campaign.

The AGRA concept was developed during Exercise 'Bumper' held in the UK in 1941, organised by the commander of Home Forces, General Alan Brooke (himself a Gunner) with Lt-Gen Bernard Montgomery as chief umpire. This large anti-invasion exercise tested many of the tactical concepts that would be used by the British Army in the latter stages of the war. The gunnery tacticians developed what became the AGRAs, powerful artillery brigades, usually comprising three medium regiments and one field regiment, which could be rapidly moved about the battlefield, and had the punch to destroy enemy artillery.

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