In 1912, Ewing moved back to Galesburg to work as a surgeon. He later moved to North Dakota, where he built a hospital and became the youngest president of the state medical society. Ewing lived in Oakland, California in the late 1930s and 1940s, and was an active member of the Kiwanis Club. In 1940, Ewing spoke at a Berkeley, California YMCA, and said attributes required of championship athletes included the "ability to rise to great heights in emergencies". Ewing was a lay leader of the Trinity Church. During the defense of the Philippines in World War II, Ewing addressed the Berkeley Kiwanis Club:"We need tough men today ... We cannot expect 100 per cent unity. There were Tories in the Revolutionary War, copperheads in the Civil War and slackers in the last war. But we can hope for that hardy leadership that characterizes our fight for freedom, our pioneering movements, our activities in World War I—yes, even the days of '49."