Shortly after the United States entered World War I, the regiment was constituted in the National Army on 18 May 1917, and organized on 16 February 1918 at Camp Stanley, Leon Springs, Texas, commanded by Colonel Lincoln Clark Andrews.

[3] The 304th was initiated (activated) on 7 October with the entire regiment located in Brooklyn, becoming part of the division's 152nd Cavalry Brigade.

[2] After the United States entered World War II, it was converted into the 63rd Tank Destroyer Battalion on 30 January 1942.

The regimental motto, "El Leon Salta" (The Lion Springs), was attached to the bottom of the distinctive unit insignia.

The regimental coat of arms was of a similar design to the distinctive unit insignia but included the Organized Reserve's Minuteman crest above the shield and omitted the motto.