He took part in the 1809 Battle of Kock, Napoleon's invasion of Russia in 1812 and in the 1830 November Uprising against the Russian Empire. On 21 December 1830 he issued a call to the Polish Jews to support the fight for Polish independence. Berkowicz was an organizer of the Jewish unit of the National Guard composed of 850 Jewish volunteers. According to Guesnet François of University Potsdam, only 100 Jewish volunteers responded to his appeal. Berkowicz was wounded on various occasions and earned two military awards of valor.