Pavlyuk Uprising

The Pavlyuk uprising of 1637 was a Cossack uprising in Left-bank Ukraine and Zaporizhia headed by Pavlo Mikhnovych against the abuses of the nobility and magnates of Polish-Lithuanian Commonwealth. The uprising was sparked by several Cossacks expelled from the Cossack Registry. Mikhnovych ordered the captured commanders of the Registered Cossacks to be executed and issued a declaration, in which he proclaimed a fight against the masters. Defeated by the forces of in the Battle of Kumeyki in 1637, he was brought to Warsaw, tried and executed. The uprising was bloodily quelled, only to restart the following year in the form of the Ostrzanin Uprising, also defeated by the Commonwealth.

It is unclear what sparked the rebellion. Most likely it was the social tension between the "Blacks", or poor peasants of the Right-Bank Ukraine, and mighty magnates like Jeremi Wiśniowiecki, who owned considerable wealth and lands in Ruthenia. Around that time local magnates tried to impose the system of pańszczyzna onto local plebeians, which rose tensions to record levels. Another reason for dissent was the number of Registered Cossacks on royal payroll, considered too small by many poor inhabitants of the region.

One of the leaders of the "Blacks", or poor peasants and non-registered Cossacks, Pavel Mikhnovych But nicknamed Pavlyuk, gathered around himself a large band of armed Zaporozhian Cossacks and reached the fortress town of Korsuń, the headquarters of the Registered Cossacks and the largest Polish royal outpost in the Borderlands. Pavlyuk had already taken part in the earlier Sulima Uprising of 1635, but was pardoned when he promised not to rise arms against the Commonwealth again.

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