Col. Phillip C. Westfahl – In the spring of 1917 when American participation in World War I became a certainty, the War Department ordered the First Wisconsin Field Artillery Battalion to be increased to a full Regiment.
The Adjutant General of the state gave instructions to have 3 new batteries recruited in Milwaukee, Green Bay, and Racine. Then Major Westfahl assumed the task, and completed it by the 1 May 1917. The Regiment would train in Camp Douglas, WI and Waco, TX as it prepared for deployment to Europe.
On 22 September 1917 the Regiment was officially made a part of the 57th F.A. Brigade, 32nd Division, and re-christened the 121st Field Artillery Regiment. COL Westfahl would go on to lead the 121st Field Artillery as it moved to Europe in March 1918.