The World War II US Army infantry division was formed with three infantry regiments, each of three battalions, a division artillery headquarters contolling four field artillery battalions, a combat engineer batalion, a mechanized cavalry reconnaissance troop, and various service and support units. The distinguishing flag for infantery divisions had horizontal stripes of scarlet and national flag blue, with the divisional shoulder sleeve insignia (SSI) centered in proper colors. The flag was made of wool bunting, 3 feet at the hoist by 4 feet on the fly. It was always carried or displayed  with a National Standard, Service of the same materials and dimensions plus a 2 1/2-inch fringe of knotted yellow silk. The division's subordinate units also has distinguishing flags or, for the infantry regiments and separate battalions, silk organizational colors. Company-sized units had guidons.

Included on this page are the flags and guidons of those units that were attached to the Big Red One on D-Day, 6 June 1944.