Mark with US Army Shoulder Sleeve Insignia: 1st | #400691

The United States Army is one of the three military departments (Army, Navy and Air Force) which reports to the Department of Defense. The modern US Army has its roots in the Continental Army, which was formed on 14 June 1775. Infantry is the branch of an army that engages in military combat on foot, distinguished from cavalry, artillery, and tank forces. A shoulder sleeve insignia (SSI), is an embroidered patch worn on some uniforms of the United States Army. The SSI in this image was approved for the 1st Infantry Division in 1918.