 Following the entry of the US into World War I, the regiment was assigned on 8 June 1917 to the First Expeditionary Division which later became the 1st Division.On 29 June 1917, the men of Company K became the first American combat unit to set foot on European soil at Saint-Nazaire, France.During the Battle of Cantigny, the 28th attacked the Germans and earned the moniker; "The Black Lions of Catigny."