He witnessed a series of battles fought between American and German troops in the Hürtgen Forest (Battle of Hürtgen Forest, September 16th - December 19th, 1944) on the German-Belgian border - the longest single battle of the U.S. Army in its history.

Hemingway was judged badly by soldiers, who accused him of posturing. He also went to Luxembourg to report on the Ardennes offensive, the last major offensive operation of the German troops during World War II. However, he arrived there suffering from pneumonia and thus did not witness the battle. However, in 1947, he was awarded the Bronze Star for valor during World War II.