LTC Peter Koster was killed in action while a prisoner of war of the Japanese Government during World War II.
Born in Krestaina, Greece, on August 15, 1889, Koster enlisted in the Army on February 4, 1911 at the age of 21. He served continuously until June 5, 1918, when he was discharged to accept a commission as a second lieutenant.
After World War I, Koster lost his officer’s commission but, deciding to remain in the Army, he enlisted on October 31, 1919 and had continuous service until he was appointed a warrant officer, Regular Army, in August 1921. At the same time, Koster also held an Infantry Reserve commission as a second lieutenant.
While he remained in the Regular Army as a warrant officer, Koster continued to be active in Reserve matters, and was promoted to captain, Infantry Reserve, in March 1926.
On October 30, 1941, Koster was promoted to Chief Warrant Officer, Regular Army. At the time, this was the highest warrant officer rank.
Koster was serving as a Chief Warrant Officer in the Philippines when World War II broke out. In February 1942, he was discharged to accept an appointment as a Captain, Judge Advocate General’s Department, with duty at Headquarters, Philippine Division, Fort William McKinley.
Koster was taken prisoner when American forces in the Philippines surrendered on May 6, 1942. On December 15, 1944, he was one of 1,619 prisoners of war in the hold of a Japanese troop ship. The vessel was en route to Japan and was in Subic Bay when it was attacked and sunk by American bombers. The Japanese had failed to mark their ship as a prisoner of war transport and consequently the naval aviators attacking the vessel did not know that their fellow Americans aboard.
Koster was posthumously promoted to lieutenant colonel.
On November 12, 2008, LTC Koster's stained glass pane was dedicated in the Hall of Heroes.