<P> The Allies failed to accomplish their objectives for the first day, but gained a tenuous foothold that they gradually expanded when they captured the port at Cherbourg on 26 June and the city of Caen on 21 July . A failed counterattack by German forces on 8 August left 50,000 soldiers of the 7th Army trapped in the Falaise pocket . The Allies launched an invasion of southern France (code - named Operation Dragoon) on 15 August, and the Liberation of Paris followed on 25 August . German forces retreated across the Seine on 30 August 1944, marking the close of Operation Overlord . </P> <P> In June 1940 Germany's leader Adolf Hitler had triumphed in what he called "the most famous victory in history"--the fall of France . British craft evacuated to England over 338,000 Allied troops trapped along the northern coast of France (including much of the British Expeditionary Force (BEF)) in the Dunkirk evacuation (27 May to 4 June). British planners reported to Prime Minister Winston Churchill on 4 October that even with the help of other Commonwealth countries and the United States, it would not be possible to regain a foothold in continental Europe in the near future . After the Axis invaded the Soviet Union in June 1941, Soviet leader Joseph Stalin began pressing for a second front in Western Europe . Churchill declined because he felt that even with American help the British did not have adequate forces for such a strike, and he wished to avoid costly frontal assaults such as those that had occurred at the Somme and Passchendaele in World War I . Two tentative plans code - named Operation Roundup and Operation Sledgehammer were put forward for 1942--43, but neither was deemed by the British to be practical or likely to succeed . Instead, the Allies expanded their activity in the Mediterranean, launching the invasion of French North Africa in November 1942, the invasion of Sicily in July 1943, and invading Italy in September . These campaigns provided the troops with valuable experience in amphibious warfare . </P> <P> Attendees at the Trident Conference in Washington in May 1943 took the decision to launch a cross-Channel invasion within the next year . Churchill favoured making the main Allied thrust into Germany from the Mediterranean theatre, but his American allies, who were providing the bulk of the men and equipment, over-ruled him . British Lieutenant - General Frederick E. Morgan was appointed Chief of Staff, Supreme Allied Commander (COSSAC), to begin detailed planning . The initial plans were constrained by the number of available landing - craft, most of which were already committed in the Mediterranean and in the Pacific . In part because of lessons learned in the Dieppe Raid of 19 August 1942, the Allies decided not to directly assault a heavily defended French seaport in their first landing . The failure at Dieppe also highlighted the need for adequate artillery and air support, particularly close air support, and specialised ships able to travel extremely close to shore . The short operating - range of British aircraft such as the Spitfire and Typhoon greatly limited the number of potential landing - sites, as comprehensive air - support depended upon having planes overhead for as long as possible . Morgan considered four sites for the landings: Brittany, the Cotentin Peninsula, Normandy, and the Pas de Calais . As Brittany and Cotentin are peninsulas, the Germans could have cut off the Allied advance at a relatively narrow isthmus, so these sites were rejected . </P> <P> Pas de Calais, the closest point in continental Europe to Britain, was the location of launch sites for V - 1 and V - 2 rockets, then still under development . The Germans regarded it as the most likely initial landing zone, and accordingly made it the most heavily fortified region . It offered the Allies few opportunities for expansion, however, as the area is bounded by numerous rivers and canals, whereas landings on a broad front in Normandy would permit simultaneous threats against the port of Cherbourg, coastal ports further west in Brittany, and an overland attack towards Paris and eventually into Germany . Normandy was therefore chosen as the landing site . The most serious drawback of the Normandy coast--the lack of port facilities--would be overcome through the development of artificial harbours . </P>

Who was in charge of the d day invasion