Some time in 1918 Leopold returned to Galicia, and immediately busied himself with creation of Polish Army. He was of Pilsudski's favourite soldiers, and a very brave soldier. During the Polish–Ukrainian War, he fought both in Eastern Galicia and Volhynia, taking part among others in the Battle of Lwów (1918). In the night of March 6/7, 1919, Kula carried out a successful attack on a Volhynian town of Torczyn, which had been in Ukrainian hands. On March 7 he died from wounds he had received during the night battle.