Bertram entered the war in France on 13th August 1914, as part of the Regimental Medical Officer's team for the 3rd Bn. Coldstream Guards. He continued to serve after the war under the service numbers 200948, then 7251037, gaining a General Service Medal with Clasp for his service in N.W. Persia. He then returned to the UK and served with 8th Coy.