 In 1915, Ross joined the army. When World War I ended he was Deputy Assistant Secretary in the Ministry of Munitions, with the rank of Major. He left the army with an OBE. Following the war, he remained for some time in public service on a part-time basis; for his efforts he was made a KBE in 1938. From 1923 to 1928 he was the Deputy White’s Professor of Moral Philosophy while John Alexander Stewart was ill. When the position became vacant in 1927, Ross refused to stand because (among other reasons) he thought his colleague H. A. Prichard a better moral philosopher (and better ‘philosopher generally’) and he preferred ‘working on metaphysics, ancient and the most modern’ (Clark 1971, 534). Two years later, in 1929, he became Provost of Oriel College, a position he held until he retired in 1947. In 1927, he was elected Fellow of the British Academy, and he served as its president from 1936 to 1940. During this time, he played a role in helping foreign scholars fleeing central Europe. In World War II he played an essential role in public service, serving on an Appeal Tribunal for Conscientious Objectors from 1940 to 1941 and on the National Arbitration Tribunal from 1941 to 1952. He served as Vice-Chancellor of Oxford from 1941 to 1944. Following the war, in 1947, he became President of the Union Académique Internationale, and, until 1949, the Chairman of the Royal Commission on the Press. In his retirement Ross continued his work in philosophy. He died in Oxford on 5 May 1971.