He rapidly ascended from the rank of osavul with the support of high-ranking older relatives during the 1750s and led a Russian-backed crackdown on haydamak peasant rebels, overseeing mass executions.

Kalnyshevsky oversaw unprecedented concentration of power into the hands of the kish otaman, abolishing the process of yearly elections which had previously governed the role.

According to Volodymyr Kuksa, a professor of history at Kyiv Polytechnic Institute, most Ukrainian researchers believe Kalnyshevsky's date of birth to be 20 June 1690.

[3] Kalnyshevsky's political career began with the patronage of the Kushchivka kurin [uk], which his older relatives, Andrii and David, were both part of.

Another relative by name of Zynovii, who was head of the Vedmedivka kurin and a representative of the Zaporozhian Sich's delegation to the Russian Empire, also may have played a role in Kalnyshevsky's rise through the ranks.

[3] Much of Kalnyshevsky's early career in politics was spent as a Zaporozhian diplomat in Saint Petersburg, where he was a member of a delegation negotiating trade relations with Russia.

The haydamaks worsened diplomatic tension that the Zaporozhian Host faced from its neighbours in spite of formal insistence that the movement was unconnected to the government.

In response, Kalnyshevsky threatened to have peasants tried in Hlukhiv, where they faced the possibility exile in Russian Siberia, rather than adhering to Ukrainian legal traditions of the time.

This force was later ordered to retreat by Hetman Kirill Razumovsky,[5] but Kalnyshevsky's rise continued; he was appointed as the kish judge [uk] the next year.

Shortly after his return from Russia, Kalnyshevsky was ordered by Governor of Kiev Ivan Glebov [ru] to crack down on the haydamaks on Zaporozhian territory.

They sought to bring the wealthy Cossacks back into power, believing them to be more likely to support Russian political aims than the Siroma.

[2] The haydamaks' spread beyond the borders of the Sich and their attacks on merchants and landowners from the Crimean Khanate and Poland–Lithuania caused alarm, and, to Russia's publicly-expressed distaste, unsuccessful attempts were made by the Siroma to keep Lantukh and Fedoriv from relenquishing the title of kish otaman.

This proposal incensed the Russian government, but due to a protracted decline in relations between Russia and the Ottoman Empire, Catherine decided against removing Kalnyshevsky from office.

Ukrainian nationalist historiography, on the other hand, has emphasised his arrest, long imprisonment and eventual death, describing him as a martyr.

A celebration dedicated to Kalnyshevsky, Kalnysheva Rada [uk], began in Romny Raion (the modern-day location of his likely place of birth) in 1991.