Chapter Text
The Golden Age of the Commonwealth came to an end in 1648 when the Cossack hetman Bohdan Khmelnytsky led an uprising of the Zaporizhian Cossacks and Ukrainian peasants against the Polish and Lithuanian magnates that ruled over them. Khmelnytsky’s uprising in 1648 was the inevitable culmination of developments starting from the inception of the Commonwealth with the Union of Lublin in 1569. Ukraine, or Ruthenia as it was commonly known back then, was a wild land with an Orthodox population ruled by the Catholic nobility of Poland and Lithuania. Since the Union of Lublin, the rights, lands, and status of the lower Orthodox classes had become increasingly threatened and encroached upon by the Catholic szlachta, who oppressed the Cossacks and the peasants by concentrating power and lands within their hands, and the introduction of Counter-Reformation practices and Jews as tax-collectors and asset managers.
Cossack desire for liberty increased after the Union of Brest in 1596. As the growing Russian state sought to acquire all the lands of Kievan Rus’, it insisted that the Metropolitan of Moscow and All Rus’ was under the authority of the Russian Church in Moscow. In response, the Orthodox eparchies of the Commonwealth (in Belarus, Ukraine, and Poland) decided to break with the Eastern Orthodox Church and place themselves under the authority of Rome instead. The Polonization of the Ruthenian church was accelerated as the Orthodox faith became persecuted and oppressed further, especially since most Ukrainians clung to their original faiths. No group hated the Union more than the Cossacks of the Zaporizhian Host, who hitherto had been faithful soldiers in the armies of the Commonwealth, participating in all the wars of the Commonwealth against the Swedes, Germans, Russians, and Turks despite the repeated ingratitude of their masters.
Khmelnytsky’s uprising set all Ukraine ablaze, as Cossack and peasant alike rose up in arms and sent the Polish magnates running for their lives. In the early days of the rebellion, the Cossack armies, accompanied by their allies the Crimean Tatars, inflicted defeat after defeat on the Polish armies, and Khmelnytsky’s ambitions of becoming the ruler and sovereign of All Rus’ began to materialize. Within a few months almost all Polish nobles, priests, and officials had been wiped out or driven away from Ukraine. However, the Cossack army suffered a terrible defeat at the Battle of Berestechko in 1651, one of the largest battles of the 17th century. With 30,000 casualties, Khmelnytsky’s forces were irreversibly damaged, and his Tatar allies abandoned him afterwards. Although the uprising was far from over, the defeat at Berestechko had made the idea of an independent Ruthenian state impossible to implement. Khmelnytsky had his revenge at the Battle of Batih, massacring many of the Commonwealth’s best soldiers in the aftermath of the battle, but his power would never regain the heights it had once reached in 1648.
Severely weakened by the uprising, two old enemies of the Commonwealth now set their sights once more on its prosperous lands. In the wake of the Thirty Years’ War, the Swedish Empire was now one of the strongest states of Europe, but it needed money to pay its large army - money that could be extracted in large quantities from a now-weakened Commonwealth. The Russian state in the north also looked on with anticipation, waiting for a perfect opportunity through which it could seize all of Ukraine in the name of Orthodox reunification, and to bring the Ukrainian Cossacks into Moscow’s sphere of influence.