"Winston Churchill flanked by the Chief of the Imperial General Staff, Field Marshal Sir Alan Brooke and General Sir Bernard Montgomery, commanding 21st Army Group, at Monty's mobile headquarters in Normandy, 12 June 1944." Left to right: The Chief of the Imperial General Staff, Field Marshal Sir Alan Brooke; Mr Winston Churchill; and the Commander of the 21st Army Group, General Sir Bernard Montgomery, at Montgomery's mobile headquarters in Normandy.