ENThis essay delves into the significance of the Khmelnytsky uprising, spotlighting it as a vivid illustration of the Polish–Lithuanian Commonwealth’s political project failure. It examines the lessons the study of the Cossack Hetmanate offers concerning the history of Poland–Lithuania. The author contends that the decline of the Commonwealth’s encompassing power, often pinpointed to 1648, likely began earlier, thus making the Union of Lublin provisions instrumental in modern Ukraine’s formation. Although the Ukrainian revolt has usually been classified as a revolution due to the sweeping economic, social, and political transformations it triggered, it could also be seen as a frontier response to integration into the more advanced economic and social structures of the Commonwealth. The author suggests that current trends in historiography invite an exploration of the uprising through the lenses of slavery, violence, and colonialism. Despite this, the national and proto-national relations between Poles and Ruthenians remain critical in the discourse. Yet, advancements in research on hybrid identities advocate moving away from binary national perspectives. It is evident that the concept of Rus’-Ukraine as a patria was established before the revolt, providing a foundation for the evolution of Cossack Ukraine into an Otchyzna. Although the Cossack Hetmanate adopted many political concepts from the Commonwealth without developing into an equally stable republic, the author asserts that Ukraine’s history must also be examined within this context. Keywords: Bohdan Khmelnytsky – Cossack uprising – Ukraine – Polish–Lithuanian Commonwealth – religious clashes – rebellion – Hetmanate – republic.