Cossak

Cossacks (Ukrainian: козаки́, kozaky, Russian: казаки́, kazaki, Belarusian: казакi, Polish: kozacy, Slovak: kozáci, Hungarian: kozákok) were a group of predominantly East Slavic-speaking people who became known as members of self-governing, semi-military communities, predominantly located in Southern Russia and in South-Eastern Ukraine. They inhabited sparsely populated areas and islands in the lower Dnieper,Don, Terek, and Ural river basins and played an important role in the historical and cultural development of Ukraine.

The origins of the first Cossacks are disputed, though the 1710 Constitution of Pylyp Orlyk claimed Khazar origin. The traditional post-imperial historiography dates the emergence of Cossacks to the 14th or 15th centuries, when two connected groups emerged, the Zaporozhian Sich of the Dnieper and the Don Cossack Host.

The Zaporizhian Sich were a vassal people of Poland–Lithuania during feudal times. Under increasing pressure from the Polish–Lithuanian Commonwealth, in the mid-17th century the Sich declared an independent Cossack Hetmanate, initiated by a rebellion under Bohdan Khmelnytsky. Afterwards, the Treaty of Pereyaslav (1654) brought most of the Ukrainian Cossack state under Russian rule. The Sich with its lands became an autonomous region under the Russian-Polish protectorate.

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Wikipedia