Designed in 1938 by Heinrich Vollmer with inspiration from its predecessor the MP 38, it was heavily used by infantrymen (particularly platoon and squad leaders), and by paratroopers, on the Eastern and Western Fronts. Its advanced and modern features made it a favorite among soldiers and popular in countries from various parts of the world after the war. It was often called "Schmeisser" by the Allies, after Hugo Schmeisser who designed the MP 18, although he was not involved in the design or production of the MP40.