The Legions took part in many battles against the forces of the Imperial Russia, both in Galicia and in the Carpathian Mountains. They suffered horrendous casualties outnumbered three to one in the Battle of Łowczówek. They captured Kielce, and in 1915 took part in the offensive on Warsaw. In June 1916 the unit had approximately 25,000 soldiers. Both the number of troops and the composition of units changed rapidly. After the Battle of Kostiuchnówka where 2,000 Polish soldiers died delaying a Russian offensive, Józef Piłsudski demanded that the Central Powers issue a guarantee of independence for Poland and partially succeeded. The Polish Legions became the Polish Auxiliary Corps. After the Act of 5th November of 1916 which pronounced the creation of the puppet Kingdom of Poland of 1916–18, the Polish Legions were transferred under German command. However, most of the members refused to swear allegiance to the German Kaiser and were interned in Beniaminów and Szczypiorno (the "Oath crisis"). Approximately 3,000 of them were drafted into the Austro-Hungarian army and the failed German "Polnische Wehrmacht", while approximately 7,500 stayed in the Austrian Polish Auxiliary Corps. They were sent to the Italian Front.