Kalnyshevsky Petro (1691 – 31 October 1803) was the last Koshovyi Otaman of the Zaporozhian Host, serving in 1762 and from 1765 to 1775. Kalnyshevsky was the Hero in the Russo-Turkish war of 1768-1774 and was honoured with a gold medal with brilliants for courage.
 
Being the leader of the Zaporozhian Host, Kalnyshevsky defended the rights of cossacks and their independence from increasing Imperial Russian influence, and encouraged agriculture development and trade in the Zaporizhian steppe.
 
After the destruction of the Zaporizhian Sich, Kalnyshevsky was arrested, tried and exiled to Solovetsky Monastery, without a right of correspondence or socialization with anyone. He was paid one rouble a day for his room and board, 40 times an average inmate. He used the money save to purchase a decorated Bible eventually inherited by the monastery. In 1792 he was transferred to solitary confinement at the Povarnya jail, where he remained until 1802.
 
Being pardoned by Emperor Alexander at the age of 110 years, Kalnyshevsky (already blind at that time) decided to remain in the monastery, where he died 2 years later in 1803.