the main British force involved. Dempsey was not Montgomery's first choice for the assignment; he had recommended that Leese take over the Second Army and Dempsey be given the First Canadian Army. There was no chance that the Canadian government would accept a British officer, and the Chief of the Imperial General Staff (CIGS), Field Marshal Sir Alan Brooke, would not countenance it. Command of the First Canadian Army was given to Canadian Lieutenant-General Harry Crerar. Leese replaced Montgomery in command of the Eighth Army on Alexander's recommendation, and Dempsey was given the Second Army on Montgomery's. Montgomery believed that while Dempsey lacked Leese's ruthlessness and drive, he was cleverer and a better tactician. Dempsey established his Second Army headquarters at Ashley Gardens in London on 26 January 1944. With his chief of staff, Brigadier Maurice Chilton, who had been part of his syndicate at Camberley, and his naval and air counterparts, Rear Admiral Sir Philip Vian and Broadhurst, Dempsey drew up the detailed plans for the assault on the British and Canadian beaches in Normandy. The Second Army made successful assaults at Gold, Juno and Sword beaches on D-Day, 6 June 1944. Dempsey came ashore that evening and established his tactical headquarters (Tac HQ) at Banville. Like Montgomery, he lived at his Tac HQ, where he maintained a small staff with some aides and liaison officers. It had caravans, radios and some vehicles, and could move at short notice. He had a staff car and an Auster light aircraft, which he called his "whizzer", and used them to move about the battlefield. Main HQ moved to Normandy on 12 June, and opened at Creully, where Montgomery had his 21st Army Group HQ. Although usually located further back than Tac HQ, it was still a field headquarters and did not require accommodation in buildings or fixed signal connections. It contained the operations, intelligence and air support branches. Where possible, Main HQ was co-located with Broadhurst's No. 83 (Composite) Group RAF and A Squadron of the GHQ Liaison Regiment (known as Phantom). Broadhurst was apprehensive when he found out that he would be Dempsey's opposite number, as their relationship in Italy had been strained, something Broadhurst attributed to Dempsey's inexperience as a corps commander. Broadhurst found that Dempsey had accepted that he had been wrong, and worked on forging the Army and RAF into a successful team. Dempsey seldom made a