The Khmelnytsky Uprising was a Cossack rebellion in Ukraine between the years 1648–1657 which turned into a Ukrainian war of liberation from Poland. Under the command of Hetman Bohdan Khmelnytsky, the Zaporozhian Cossacks allied with the Crimean Tatars, and the local peasantry, fought several battles against the armies and paramilitary forces of the Polish–Lithuanian Commonwealth. The result was the end of Polish szlachta control and of ecclesiastical jurisdiction for the Latin Rite Catholics and arendators) over the region. The Uprising has taken on a symbolic meaning in the story of Ukraine's relationship with Russia. It resulted in the incorporation of eastern Ukraine into the Tsardom of Muscovy at the Pereiaslav Agreement, where the Cossacks swore an oath of allegiance to the tsar. This, according to the poet and artist, Taras Shevchenko, brought about his people's 'enslavement' under Russia.
The Uprising started as the rebellion of the Cossacks, but as other Orthodox Christian classes (peasants, burghers, petty nobility) of the Ukrainian palatinates joined them, the ultimate aim became a creation of Ukrainian autonomous state. The Uprising succeeded in ending the Polish influence over those Cossack lands that were eventually taken by the Tsardom of Russia. These events, along with internal conflicts and hostilities with Sweden and Russia, resulted in severely diminished Polish power during this period (referred to in Polish history as The Deluge). The failure of the Cossacks to consolidate their victory led to the Ruin (Ukrainian history).