220 years ago, the last kish otaman of the Zaporozhian Sich, Petro Kalnyshevsky, passed away. Modern society is increasingly in need of spiritual leaders who would serve as examples of high sincerity, honesty, justice, and love. The righteous life of P. Kalnyshevsky can become a spiritual authority for the moral improvement of society. Proof of this is the Orthodox Church of Ukraine's canonization of the Cossack otaman in July 2008. The capture and destruction of the Zaporozhian Sich has much in common with Russia's annexation of Crimea, the war in eastern Ukraine, and the large-scale Russian aggression against Ukraine that began on February 24, 2022. The article will help to better understand the policy of the Russian regimes towards Ukraine, the origins of the war, and dispel ideological myths. Studying and taking into account the experience of the past (positive and negative), drawing lessons from it, is considered an important task of scholars, the successful solution of which is impossible without extensive historiographical research. The article reveals the most important milestones in the life of the last kish otaman of the Zaporozhian Sich, Petro Kalnyshevsky (1691-1803). Attention is focused on his state, economic, military and charitable activities. P. Kalnyshevsky consistently defended the land interests and borders of the Zaporozhian Sich, actively settled the southern Ukrainian steppes, and contributed to the establishment of new settlements. He cared about the development of agriculture, crafts, and trade. Countering Russian expansion, P. Kalnyshevsky managed to implement a new progressive system of management that included the development of farms, the creation of Cossack winter quarters, and the rise of crafts, foreign and domestic trade. This, in turn, served as one of the main reasons for the liquidation of the Zaporozhian Sich, which hindered Russian economic interests in southern Ukraine. The military activities and military talent of the Cossack otaman, his participation in the Russian-Turkish wars of the eighteenth century are being revealed. Also, Kalnyshevsky's charity and his valuable gifts to spiritual shrines are being described. The Gospel, made at the expense of the otaman and presented to the church monastery, is described separately. Attention is drawn to P. Kalnyshevsky's solovetsky imprisonment, the terrible conditions of detention.