Ostryanyn Uprising

The Ostryanyn uprising was a 1638 Cossack uprising against the Polish–Lithuanian Commonwealth. It was sparked by an act of the Sejm (legislature) passed the same year that declared that non-Registered Cossacks were equal to ordinary peasants in their rights, and hence were subjected to enserfment. The uprising was initially led by Cossack Hetman Yakiv Ostryanyn (Polish: Jakub Ostrzanin) but was eventually crushed.

According to a chronicle of 1864 written by Samuil Velichko, Ostryanyn, who had just been elected Hetman, issued an address to the Little Russian people on the eve of the campaign in March 1638. He declared that he would "go with his army to the Ukraine in order to liberate the Orthodox people from the yoke of oppression and torment of the Polish tyranny and claim vengeance for grievances, ruin and torturous abuse... suffered by the entire Russian populace, living on both sides of the Dnieper."

Ostryanyn also called on the people of Ukraine to join the insurgency and to beware of the Registered Cossacks. His leaflets were spread across Ukraine, reaching as far as Pokuttya. His appeal was carried and distributed by the Cossack elders, bandurists, youth, and according to Ostryanyn, even Orthodox monks. People began to prepare for an uprising, some going to Zaporozhye, while others sent food, money, and gunpowder.

The rebels left Zaporozhye and divided themselves into three detachments. The first, moving down the left bank of the Dnieper, was led by Ostryanyn himself. His force took Kremenchuk and moved on to Khorol and Omel'nyk. The second body of troops, consisting of a flotilla led by Guney, took the river crossings in Kremenchug, Maksimovka, Buzhin and Chigirin. The third force occupied the right bank of the Dnieper.

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