Hetman of Zaporizhian Cossacks is a historical term that has multiple meanings.
Officially the post was known as Hetman of the Zaporizhian Host (Ukrainian: Гетьман Війська Запорозького, Hetman Viiska Zaporozkoho).[1] Hetman of Zaporizhian Cossacks as a title was not officially recognized internationally until the creation of the Cossack Hetmanate. With the creation of Registered Cossacks units their leaders were officially referred to as Senior of His Royal Grace Zaporozhian Host (Ukrainian: старший його Королівської Милості Війська Запорозького, Starshyi Yoho Korolivskoi Mylosti Viiska Zaporozkoho).[1] Before 1648 and the establishment of the Cossack Hetmanate there were numerous regional hetmans across the Dnieper-banks, who usually were starostas or voivodes.
The first widely recognized hetman of Zaporizhia was Dmytro Vyshnevetsky, after that several Polish starostas were added to the Hetman registry such as Lanckoroński and Daszkiewicz who also led their own cossack formations. According to Mykola Hrushevsky they were not really considered as hetman, at least by their contemporaries. Among other such starostas were Karpo Maslo from Cherkasy, Yatsko Bilous (Pereiaslav), Andrushko (Bratslav), and many others. Even Princes Konstanty Ostrogski and Bohdan Hlinski were conducting Cossack raids on Tatar uluses (districts).
The commanders of Zaporozhian Host (the Kish) often considered as hetmans in fact carried a title of Kish Otaman. As from 1572,[2] hetman was the unofficial title of commanders of the Registered Cossack Army (Ukrainian: Козаки реєстрові, Polish: Kozacy rejestrowi, Russian: Казаки реестровые) of the Polish–Lithuanian Commonwealth. From the 1648 Bohdan Khmelnytsky uprising, Hetman was the title of the head of the Cossack state, the Cossack Hetmanate. Cossack hetmans had very broad powers and acted as supreme military commanders and executive leader (by issuing administrative decrees).
After the split of Ukrainian territory along the Dnieper River by the Polish-Russian Treaty of Andrusovo 1667, there was an introduction of dual leadership for each bank, or for each Ukraine of Dnieper (left and right). After the Treaty of Andrusovo there existed two different Cossack Hetmanates with two Hetmans the one in Poland being called Nakazny Hetman of His Royal Mercy of Zaporizhian Host and the Russian one titled Hetman of His Tsar's Mercy of Zaporizhian Host.
Eventually the official state powers of Cossack Hetmans were gradually diminished in the 18th century, and finally abolished by Catherine II of Russia in 1764.