In February 1918, after the signing of Treaty of Brest, he was the initiator of the rebellion of 2nd Legion Brigade and its breakthrough through the front during the Battle of Rarańcza. Then he handed over the command of this formation to General Józef Haller. After the front had passed, he became the chief of staff of the Polish II Corps in Russia following his promotion to the rank of colonel. After the corps was disarmed by the Germans after the Battle of Kaniów in May 1918, he served in command positions in the Polish Military Organization in Russia. He was the commander of the 2nd Infantry Regiment in the 4th Polish Rifle Division.