The battalion was activated on 20 November 1917 at Quantico, Virginia as the 9th Regiment. During December 1917 they were deployed to Guantanamo Bay, Cuba, and attached to the 3rd Provisional Brigade.
On 20 November 1917, the battalion was established at Quantico, Virginia as the 9th Regiment. In December 1917, it moved to Guantanamo Bay, Cuba, and joined the 3rd Provisional Brigade.