 Despite initial successes, the Cossacks started to lose ground and were ultimately defeated by Polish-led "levée en masse" in the battle of Piątek near Zhitomir.By 1593 the rebellion was quelled and Krzysztof Kosiński killed.Nalyvaiko, who initially served in private units of Janusz Ostrogski, took an active part in the suppression of the uprising.