Stephen B. Schoolfield began his military career by joining the 1st Kentucky Volunteer Regiment, Company F, on May 26, 1898 and participating in the Spanish-Amerian War serving with distinction in the campaign in Cuba. He later served in the regular Army in the Philippine Islands during the Insurrection there and later saw action (at temporary rank of Captain) while serving (September 1918 to June 1919) with the AEF in France during World War I. He was then assigned to serve (September 1919 to April 1920) with Major General William S. Graves in Siberia supporting the White Russian Army’s fight against the Bolsheviks’ Red Army.

Warrant Officer Stephen B. Schoolfield was promoted to Captain upon his retirement from the Army on October 31, 1931, after more than thirty years of service.

“American Expeditionary Force (Siberia)
In July 1918 President Woodrow Wilson decided to intervene in Russia and ordered eight thousand AEF troops to Siberia to protect U.S. supplies along the Trans-Siberian railroad. Chaos and uncertainty prevailed in Russia at this time. The Russian tsar had been overthrown by the revolution led by Alexander Kerensky in February-March 1917 (eventually to be ousted by the Bolsheviks in November 1917), raising Wilson's hopes for democratizing Russia and spreading capitalism. After the fall of the tsarist government the U.S. recognized the Russian Provisional Government, providing it with money and aid. Railroad officers, skilled technicians under the Russian Railway Service Corps, and railway equipment were sent to assist in operating the Trans-Siberian railroad. Control of the railroad was extremely important because it served as the only major logistics and communication line across Russia. The eastern port of Vladivostok held more than $1 billion of supplies and material that had been sent to Russia as support for that country's eventually unsuccessful war effort. Both the French and British actively pressed Wilson to send troops to Siberia to create diversions on the Eastern front that could lessen German and Austrian troop strength on the Western front.

Commander of the U.S. forces in Siberia was Major General William S. Graves, a training officer in California. Graves' orders (an aide-mémoire drafted by Wilson) instructed him to facilitate the safe exit of the forty-thousand-man Czech Legion from Russia, guard the nearly $1 billion worth of American military equipment stored at Vladivostok and Murmansk, and help the Russians organize their new government. The first troops arrived in Vladivostok in August 1918 and Graves followed in September. Japan also sent seventy thousand troops to protect supplies and communication and destabilize the Russian government as a means to acquire Siberian and Manchurian economic resources. Conditions were extremely chaotic along the railroad as a result of the Russian civil war. An agreement to operate the railroad was reached by the Allied governments participating in the Siberian intervention in November 1918. It was implemented in April 1919. Three countries, Japan, the United States and China, were given a sector of the railroad to guard.

The end of World War I in November 1918 did not mean homecoming for the AEF forces in Siberia. Wilson wanted to pursue a "wait and see" policy until the Paris peace conference concluded before deciding which of several Russian governments to recognize and whether to withdraw the AEF from Vladivostok.

The AEF spent two years in Siberia hampered by larger Japanese and Cossack forces, unclear and incomplete instructions, and Graves' own commitment to strict political neutrality. The eventual defeat of White Army forces by the Bolshevik Red Army led to demands from the U.S. Congress for complete withdrawal of American troops. The AEF forces left Siberia beginning in March 1920; Graves left with the last troops on April 1, 1920. The American Expeditionary Force (Siberia) served under combat conditions longer than any force involved in World War I and was the first and only American military unit sent to Russian soil.”