Background
He was born in Newport, Kentucky, United States, on December 31, 1860.
He was born in Newport, Kentucky, United States, on December 31, 1860.
He graduated from West Point in 1882.
He entered the Ordnance Department in 1890. He retired from active service in 1914 as a colonel, but was recalled as chief of the Small Arms Division of Ordnance during World War I and was promoted to brigadier general in 1918. At the end of the war he retired again and entered business.
During his years of active service Thompson invented a number of semiautomatic rifles, but none of these proved successful. In 1920, however, the Thompson machine gun, or "Tommy gun, " was developed and marketed. This was a 45-cal. submachine gun, weighing about 10 pounds (4. 5 kg), with full automatic or semiautomatic fire, and was among the first of its type to be made in the United States.