It was officially organized as the First Expeditionary Division on 8 June 1917, under the command of Brigadier General William L. Sibert, just a few weeks after the entrance of the United States into World War I. Units of the division began sailing for France on 14 June. On 6 July, the division's name was changed to its present form. The division first went into battle on 23 October.
In World War II, the division landed in Oran, Algeria as part of Operation Torch, fought in the Tunisian campaign, then in Operation Husky in Sicily. It was the division that stormed Omaha Beach on D-Day, and eventually went all the way to Czechoslovakia.
The division also participated in Operation Desert Storm, rolling over the Iraqi 26th Infantry Division and taking 11,400 prisoners in four days.