By 1241, having conquered large parts of Russia, the Mongols continued the invasion of Europe with a massive three-pronged advance, following the fleeing Cumans, who had established an uncertain alliance with King Bela IV of Hungary. They first invaded Poland, and finally, Hungary, culminating in the crushing defeat of the Hungarians in the Battle of Mohi. The Mongol aim seems to have consistently been to defeat the Hungarian-Cuman alliance. The Mongols raided across the borders to Austria and Bohemia in the summer when the Great Khan died, and the Mongol princes returned home to elect a new Great Khan.