Development of the .50 caliber Vickers guns began during World War One, but stagnated after 1918, and was not really completed until the early 1930s. At that point, Vickers produced a series of the guns for use primarily as armored vehicle armament and for antiaircraft use. It was formally adopted in 1933, and declared obsolete in 1944. A total of 1,117 were made for ground use, plus more for naval use. The ground guns ran from MkI to MkV, with today’s example being a MkIV.