Battle of Berestechko
The Battle of Berestechko was fought between the Ukrainian Cossacks, led by Hetman Bohdan Khmelnytsky, aided by their Crimean Tatar allies, and a Polish army under King John II Casimir. It was a battle of a Cossack rebellion in Ukraine that took place in the years 1648–1657 after the expiration of a two-year truce.