The 29th Division was constituted on 18 July 1917 within the National Guard. It was formed with troops from four states—Maryland, Virginia, Delaware, New Jersey—and the District of Columbia. The shoulder sleeve insignia, authorized in 1918, reflects the cohesive integration of Soldiers from multiple states throughout the mid-Atlantic region. The interlocking Yin and Yang design of blue and gray signify the unification of our Nation to defeat a common enemy.