Operation Roundup
The operation Roundup was one of the British in the early stages of World War II, worked out in 1941 enterprises to invasion in Western Europe , which from the spring of 1942 by the combined planning staffs of the British and Americans continue and along with the plan for Operation Sledgehammer in April 1942 Management levels was presented.
In contrast to Operation Sledgehammer, Roundup was a plan for a significantly expanded invasion, which in its main features already corresponded to the later Operation Overlord or Operation Neptune . The execution was scheduled for the first half of 1943. For this purpose, the USA wanted to set up a 1 million strong invasion force in Great Britain in the course of Operation Bolero .
1941
The first draft of the British in 1941 drafted a scenario for an invasion that was to take place with relatively few equipment and soldiers. A demoralized Third Reich was assumed, which would no longer believe in a victory and would withdraw all forces to defend its own territory . Beaches east of Le Havre to Dieppe were intended as landing zones . The aim was to capture an area between Calais and the Seine that protruded 75 to 100 miles inland. The invading army would then conquer Antwerp further north and penetrate into Germany via the Meuse near Liège . A total of 6 1/3 infantry divisions , 6 tank divisions and 6 tank brigades with the respective supply units were provided for the advance. For the coastal bombing, the British only planned three ships, including a battleship . This shows how little German resistance was expected and what little understanding of the military or strategy the British had at that time.
The 1941 version of the Roundup plan was not seriously pursued and was never officially presented to management levels.
After the ARCADIA conference in Washington, DC on December 31, 1941, the British Prime Minister Winston Churchill and the American President Franklin D. Roosevelt reaffirmed the previously established premise “Germany first”, despite the recent entry of the USA into the war ). Serious joint consultations began to work out the attack plans.
1942
Depending on the perspective of the other, the plans were based on two aspects. The British, who were closer to the war and saw their own country threatened, put their main focus on the difficulties of an invasion attack with all logistical and tactical problems. In return, the Americans, who were some 3,000 miles away from the action, tended to focus more on global strategy, as they also had to consider the Pacific region through the war with Japan. Each of these perspectives made an important contribution to the structure of the plan. Both sides agreed on one thing; the sooner the initiative of the Axis powers could be contained, the sooner it was possible to reduce superfluous defense resources and make them available to a powerful offensive army.
In January 1942, Churchill and Roosevelt favored a first invasion plan for the landing in North Africa , Operation Gymnast , but this was dropped in March because the US had to become more involved in the Pacific than planned.
The American planning staff now began to work out Operation Sledgehammer to form an Allied Western Front . The entire operation, however, depended on whether the USSR could tie up the German forces or even strike back.
Roundup planning by General Marshall
On March 25, 1942, Roosevelt summoned Secretary of War Henry L. Stimson to the White House to inquire whether US troops might be better deployed in North Africa or northwest Europe in future offensives. He received the reply from the War Department from General George C. Marshall on April 2. He presented the President with a complete plan for a crossing of the English Channel in 1943.
The plan provided for a tripartite division of the operation, the preparatory phase, the actual canal crossing with the construction of bridgeheads between Le Havre and Boulogne-sur-Mer and finally the merging and expansion of the bridgeheads. Logistics set the earliest possible start of phase two on April 1, 1943, while the preparatory phase - the organization, arming and embarkation of the necessary troops - could begin immediately. In the summer of 1942, small vanguard units were to land on the accessible enemy coasts, which, according to Marshall, were supposed to "build up an active front" . On the one hand, German soldiers could be withdrawn from the Russian front in order to make a contribution to Stalin's relief and, on the other hand, they should increase the Germans' fear that one of the small bridgeheads could lead to an extensive invasion.
For the main invasion, which was planned for the spring of 1943, 48 divisions were planned, which were to be supported by 5,800 combat aircraft . The landing beaches should be between Étretat north of Le Havre and Cap Gris-Nez and the main attack wedge on both sides of the Somme estuary . From there it was planned to expand the bridgeheads up to the capture of Le Havre and up to the Seine. Marshall's plan also specifically defined the strategy for the production, training, provision and shipping of the units. There was still enough planning time, but the decision for the plan should be made quickly, since according to the current production figures, the USA would only be able to manufacture and deliver about 10% of the landing craft by the planned time of the invasion.
In the second week of April, Marshall and a direct agent from Roosevelt went to London to get the British planning team to reach a decision as quickly as possible. Within very brief consultations, an agreement was reached on all points.
In mid-June 1942, Churchill and Roosevelt agreed to carry out the American plan for Operation Sledgehammer , which included a small bridgehead at Cherbourg for supplies. Just 14 days later, Churchill rejected his decision at another meeting and now proposed to carry out Operation Roundup .
For Roundup , 8,200 small landing craft were to be stationed in British ports to cross the canal. The British themselves saw the small boats as a danger to the troops, as they knew the rough seas in the English Channel better than the Americans. At a meeting of the planning staff in May 1942 they succeeded in convincing the USA to use the LSTs to build larger seaworthy landing ships in order to be able to bring more soldiers to the French coast more safely . The US Navy , however, was very busy at this time so that, for the Pacific War transport ships and submarines to build. This led to longer delays and when the first landing craft were launched, they were needed for training the troops. It quickly became apparent that in the spring of 1943 no adequate landing fleet could be put together for Operation Roundup .
1943
Since the Roundup plan had won over both sides, it was not dropped, it was only postponed. The British Lieutenant-General Sir Frederick E. Morgan , who later became COSSAC , significantly expanded the plan from March 1943 under the name Roundhammer . The SHAEF staff took the outline of the plan Morgan developed and shaped it into the final version, Operation Overlord .