Mongols had made a treaty with Galicia-Volhynia , whose prince was therefore taken by surprise when the Mongols suddenly attacked in December 1240. Kiev, Vladimir, and other cities were quickly taken. Invasion of Central Europe (1241–1242) The attack on Europe was planned and carried out by Subutai, who achieved his lasting fame with his victories there. Having devastated the various Russian principalities, he sent spies as far as Poland, Hungary, and Austria in preparation for an attack into the heartland of Europe. Having a clear picture of the European kingdoms, he brilliantly prepared an attack nominally commanded by Batu Khan and two other princes of the blood. While Batu Khan, son of Jochi, was the overall leader, Subutai was the actual commander in the field, and as such was present in both the northern and southern campaigns against Kievan Rus'. He personally commanded the central column that moved against the Kingdom of Hungary, and likely gave detailed instructions to his subordinates. Though the Mongol methods of warfare were mostly a mystery in the west, the King of Hungary, Bela IV, was well-informed of the Mongol invasion of Russia and prepared as well as the fractured relations of Europe would allow him to. Though Bela was unable to obtain help from the Holy Roman Empire or the Pope, he did at least have the support of his cousins in Poland. Once again, Subutai invaded during winter, when they would be least expected. The Mongol invasion of Europe was a five-pronged attack. Kaidu and Orda Khan ravaged Northern Poland, Baidar Southern Poland, while Shiban attacked through the rugged terrain in northeastern Hungary, Subutai and Batu invaded central Hungary, and Guyuk marched south through Transylvania. The Mongols dispersed their forces in order to confuse the Europeans as to their ultimate objectives, and defeat the European armies piecemeal before they could mass into a central force. After a series of sweeping victories Baidar and Kadan regrouped their northern force and defeated the main Polish army at the Battle of Legnica, right before it could merge with the Bohemian Army a days march away. While Güyük's army triumphed in Transylvania, a day after Legnica, Subutai was waiting for the Hungarian army on the Hungarian plain. Though the Hungarian King Bela IV had effectively blocked the Carpathian passes using felled trees, ditches, traps, and other natural obstacles, in addition to the general disrepair or simple nonexistence