The Lewis Gun was developed by Colonel Isaac Lewis, U.S.A. from the designs of George MacLean. It was first accepted into military service by the Belgians in 1913 and soon found it's way into the British service. The Lewis was the first light machinegun to be used in great numbers in warfare. It is a shoulder or bipod fired, air cooled weapon with a gas piston operating system of fairly complicated design and easily prone to malfunction. This and it's excessive weight were its chief drawbacks. Inspite of its shortcomings it was immensely popular with its users.

"I wouldn't part with my Lewis for the world.
 That's the thing that gives Jerrie (sic)
 his iron rations whenever he tries to come over.
 It never fails to stop him"
George Fetherolf, I Company, 107th Infantry

In U.S. Army units that used the Lewis Gun it was an organic part of the 59 man infantry platoon. The platoon's 4th section was an automatic riflemen section consisting of a sergeant, 2 corporals (each in charge of two guns), 4 Lewis gunners (pfc's) and 8 riflemen (pvts). In an assault the firepower of the Lewis was greatly appreciated and very effective.