In January 1648, a major anti-Polish uprising led by Bohdan Khmelnytskyi began in the Zaporizhia lands. Supported by popular masses and by Crimean Khanate the rebels won a number of victories over the government forces of the Polish–Lithuanian Commonwealth seeking the increase of Cossack registry (kept at the expense of the state treasury), weakening of the Polish aristocratic oppression, oppression by the Jews who governed estates as well as recovery of positions of the Orthodox Church in own lands. However, the autonomy obtained by Khmelnytsky found itself squeezed between three Great powers: Polish–Lithuanian Commonwealth, Tsardom of Russia and Ottoman Empire.