This large transport glider was made under the directions of the German army at the beginning of World War II. In 1940, during the drafting of plans for an invasion of England, the necessity to quickly move large amounts of troops and equipment emerged. This was not achievable with the ships and standard Ju 52 transport aircraft which were in use at the time. In December 1940, following the failure of the plan to invade England, Germany began its attack on Russia, and, once again, found the need to rapidly move troops and equipment, due to the great distances and lack of suitable roads. The Me 321 entered into service in June 1941. With its ability to carry 130 equipped soldiers or an IV Panzer tank, it appeared to be the perfect solution for the German general staff. However, a number of problems immediately emerged. There were no aircraft capable of towing this giant glider and the use of no fewer than 3 twin-engine Bf 110s was required for a single glider, which meant removing them from their position on the front line; due to its heavy weight, the Me 321 was unable to repeat the landing procedure in the event of an error, special equipment was required to move it on the ground and it also required large areas for take-off and landing. In an attempt to solve these problems, various solutions were developed, such as the use of rockets to increase the take-off thrust and the creation of a special version of He111 bomber, achieved by the union of two aircraft with 5 engines (He 111 Zwilling) to create a powerful tow plane. Despite these solutions, the use of the Me 321 was still extremely limited due to the lack of adequate landing areas and the limited availability of tow planes. In order to resolve these problems, the Me 323 version, powered by six engines and based on this large glider, was subsequently designed.