The 199th Infantry Brigade (Light) is a unit of the United States Army which served in the Reserve from 1921–1940, in the active army from 1966 to 1970 (serving in the Vietnam War), briefly in 1991–1992 at Fort Lewis, and from 2007 as an active army training formation at Fort Benning. During 1969, the 199th was responsible for the security of the region north and east of the capital, and in 1970 moved into the "Iron Triangle" when other units participated in the Cambodian Incursion.