in january 1915, one day before he was called up for military service in world war i, he married rosa koch. at the beginning of 1915, he was posted to the artillery on the western front, where he stayed till the end of the war, during the course of which he was wounded twice. he said that he fought in the following battles: battle of champagne (1915–1916), battle of the somme (1916), second battle of the aisne, battle of soissons, battle of cambrai (1917) (1917) and battle of arras (1917).