Zhmaylo Uprising

The Zhmaylo uprising (Polish: Powstanie Żmajły) was a Cossack rebellion headed by Marek Zhmaylo against the Polish-Lithuanian Commonwealth in 1625. On 5 November Marek Zhmaylo was deprived of his title and Hetman Mykhailo Doroshenko was chosen to sign the Treaty of Kurukove, pledging allegiance to the Crown of the Kingdom of Poland.

In the late 16th century Poland introduced the institution of the Registered Cossacks, which granted some privileges to the militant Cossack people inhabiting territories of today Ukraine, then mostly controlled by Poland. Cossacks were allowed to serve in special units in the Polish military, but during the times of peace the Poles intended to reduce the number of Cossacks on the register and turn them into peasants. This happened again after the Polish-Ottoman War, in which aftermath the 40,000 mobilized Cossacks led then by Hetman Petro Konashevych-Sahaidachny were reduced to 5,000.

In response, the Cossacks began diplomatic endeavors with their Commonwealth neighbors, including the Tatars and the Muscovy. The Polish-Lithuanian government sent a special commission headed by Hetman Stanisław Koniecpolski, but two attempts to negotiate a truce failed. In September 1625 Koniecpolski gathered an army to quell the unrest.

According to Leszek Podhorodecki, his forces numbered about 12,000, with 30 artillery pieces; and were composed of the regular army boosted by Registered Cossacks and forces of local nobility, both the pospolite ruszenie and some chorągiew units sponsored by the magnates. The Cossack leader Marek Zhmaylo had numerical superiority, gathering about 20,000 men under his banners.

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