The Cossack Hetmanate, officially the Zaporizhian Host or Army of Zaporizhia, was a Cossack state in the region of what is today Central Ukraine between 1648 and 1764 (although its administrative-judicial system persisted until 1782).

The Hetmanate was founded by the Hetman of Zaporizhian Host Bohdan Khmelnytsky during the Uprising of 1648–57 in the eastern territories of the Polish–Lithuanian Commonwealth. Establishment of vassal relations with the Tsardom of Russia in the Treaty of Pereyaslav of 1654 is considered a benchmark of the Cossack Hetmanate in Soviet, Ukrainian, and Russian historiography. The second Pereyaslav Council in 1659 further restricted the independence of the Hetmanate, and from the Russian side there were attempts to declare agreements reached with Yurii Khmelnytsky in 1659 as nothing more than the "former Bohdan's agreements" of 1654. The 1667 Treaty of Andrusovo – conducted without any representation from the Cossack Hetmanate – established borders between the Polish and Russian states, dividing the Hetmanate in half along the Dnieper and putting the Zaporozhian Sich under a formal joint Russian-Polish administration.

After a failed attempt to break the union with Russia by Ivan Mazepa in 1708, the whole area was included into the Government of Kiev and Cossack autonomy was severely restricted. Catherine II of Russia officially abolished the institute of the Hetman in 1764, and in 1764-1781 the Cossack Hetmanate was incorporated as the Little Russia Governorate headed by Pyotr Rumyantsev, with the last remnants of the Hetmanate's administrative system abolished in 1781.