The MP 38 and MP 40 often called Schmeisser, were submachine gun

Submachine gun

A submachine gun is an automatic carbine, designed to fire pistol cartridges. It combines the automatic fire of a machine gun with the cartridge of a pistol. The submachine gun was invented during World War I , but the apex of its use was during World War II when millions of the weapon type were...

s developed in Nazi Germany

Nazi Germany

Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...

 and used extensively by paratrooper

Paratrooper

Paratroopers are soldiers trained in parachuting and generally operate as part of an airborne force.Paratroopers are used for tactical advantage as they can be inserted into the battlefield from the air, thereby allowing them to be positioned in areas not accessible by land...

s, tank crews, platoon

Platoon

A platoon is a military unit typically composed of two to four sections or squads and containing 16 to 50 soldiers. Platoons are organized into a company, which typically consists of three, four or five platoons. A platoon is typically the smallest military unit led by a commissioned officer—the...

 and squad

Squad

In military terminology, a squad is a small military unit led by a non-commissioned officer that is subordinate to an infantry platoon. In countries following the British Army tradition this organization is referred to as a section...

 leaders, and other troops during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

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The MP 40 descended from its predecessor, the MP 38, which was in turn based on the MP 36, a prototype made of machined steel. The MP 36 was developed independently by Erma Werke

Erma Werke

Erfurter Maschinenfabrik was a German weapons manufacturer founded in 1922 by Berthold Geipel. Prior to and during World War II they manufactured many firearms, including the K98k, MP40, and several other SMGs....

's Berthold Geipel with funding from the German Army

German Army

The German Army is the land component of the armed forces of the Federal Republic of Germany. Following the disbanding of the Wehrmacht after World War II, it was re-established in 1955 as the Bundesheer, part of the newly formed West German Bundeswehr along with the Navy and the Air Force...

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