Original: Hitler served in France and Belgium in the 16th Bavarian Reserve Regiment (called Regiment List after its first commander), ending the war as a Gefreiter (equivalent at the time to a lance corporal in the British and private first class in the American armies).
Simplified: He fought for Germany in World War I. Hitler served in Belgium and France in the 16th Bavarian Reserve Regiment. On 1 November 1914, Hitler became a Gefreiter (equivalent at the time to a private first class in the American and lance corporal in the British armies).