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History

Thompson Submachine Gun

What is thompson submachine gun?

· Emily Grant

Key facts

Inventor John T. Thompson[1]
Design date 1918[1]
Patent date 1920[3]
Common nickname Tommy gun[1]
Adopted by U.S. Army 1928[3]

The Thompson submachine gun is a submachine gun invented by John T. Thompson in 1918–1920, designed for World War I trench warfare and later known as the “Tommy gun”.

Context

The Thompson submachine gun, invented by John T. Thompson in 1918–1920, was designed for World War I trench warfare and later became widely known as the “Tommy gun” [1]. It was patented in 1920 [3]. The weapon was intended to break the stalemate of trench warfare [1]. It saw early use by the U.S. Marine Corps, U.S. Postal Inspection Service, Irish Republican Army, Republic of China, and FBI [1]. The U.S. Army adopted it in 1928 [3]. During the U.S. Prohibition era, it became infamous for use by gangsters [3]. The term “submachine gun” is said to have been used in the Thompson’s name first [2].

Documented claims

  • The Thompson submachine gun was designed to break the trench-warfare stalemate of World War I. [1]
  • It became infamous during the U.S. Prohibition era for use by gangsters. [3]
  • The term “submachine gun” is said to have been used in the Thompson’s name first. [2]

Questions and answers

Can you still get a Thompson submachine gun?

Yes, but ownership is regulated by the National Firearms Act in the U.S. [3].

How much is a Tommy gun worth today?

Prices vary widely, but original Thompsons can be very expensive due to their historical value [3].

How many rounds did a Tommy gun hold?

The Thompson used box magazines of 20 or 30 rounds, and drum magazines of 50 or 100 rounds [3].

What is special about the Thompson gun?

It was one of the first submachine guns and is famous for its role in Prohibition-era crime and World War II [3].

Sources

  1. Tommygun Inventor — explorekyhistory.ky.gov (retrieved August 3, 2026)
  2. A Look Back at the Thompson Submachine Gun — americanrifleman.org (retrieved August 3, 2026)
  3. Original manufacturer of the world famous "Tommy Gun" — auto-ordnance.com (retrieved August 3, 2026)

Sources last checked August 3, 2026. · More in History