The United States went into World War Two with the Thompsons submachine gun – a weapon far too heavy and too expensive for its role. The British went to the other extreme with the Sten and while the US did not want a gun quite that crude, the Sten did spur a desire for something cheaper than the Thompson. George Hyde (the working for the Inland Division of GM) had worked on submachine gun designs in the 1930s, and he put together a weapon that would fit US needs. It was much cheaper than the Thompson and weighed in a full 2 pounds lighter. At tests in the spring of 1942, it also proved to be much more accurate in automatic firing, as it had a much more ergonomic stock design than the Thompson. The weapons was approved as the M2 submachine gun in 1942, and a contract went to Marlin to produce it (Inland had no extra production capacity at the time).
The receiver of the M2 was made through a metal sintering process, and Marlin had trouble getting this properly tooled up. The first gun delivery didn’t actually happen. Until May or 1943, and by that time Hype had finished designing the M3 “Grease Gun”, which was cheaper still, and more attractive to the military. The contract for the M2 was cancelled in June of 1943, with only 400 guns delivered. There are only six known surviving examples today, split between private collections, museums, and military institutions.