Ukrainian People's Army
Oleksander Petrovych Hrekov () (4 December 1875 – 2 December 1958) was a general of the Imperial Russian Army, Ukrainian People's Army, military professor and one of the most prominent personalities in the History of Ukraine. He was better known as the commander-in-chief of the army of the West Ukrainian National Republic during the Polish-Ukrainian War and architect of the Chortkiv offensive in which the Ukrainian Galician Army advanced against the Polish army.