Complex sentence: Also formally under command of Poniatowski was Major General Józef Orłowski, the commander of the fortress of Kamieniec Podolski with 3,374 soldiers, but he did not take active part in the war and surrendered to the Russians when ordered by the Polish King Stanisław Poniatowski.
Split into simpler sentences: Also formally under command of Poniatowski was Major General Józef Orłowski, the commander of the fortress of Kamieniec Podolski. He commanded 3,374 soldiers, but he did not take active part in the war and surrendered to the Russians when ordered by the Polish King Stanisław Poniatowski.