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 of roads in eastern Hungary, Subutai's force still managed an astonishing pace of a day despite several feet of snow. The Mongols retained a pioneer corps capable of efficiently clearing pathways through the forest, and were unfazed by Bela's obstacles. Only one day after the smaller Mongol army in
Poland had won the
Battle of Legnica, Subutai launched his attack, thus beginning the
Battle of Mohi during the night of 10 April 1241. At Mohi, the Mongols fixated the Hungarian attention in the center by assaulting the lone bridge and attempting to ford to the north and around the bridge. The main body began to cross the Sajo by the bridge at Mohi, and continued to attack the following day. This was met with fierce resistance, so
catapults were used to clear the opposite bank of crossbowmen, as was noted earlier. Meanwhile, Subutai in secret created a pontoon bridge to the south, where the river was too deep to be forded, and crossed the river in secret with a large force. When the crossing was completed, the second contingent attacked from the south, and a third from the north. The threat of now reassembled Mongol force, enveloping the Hungarian army on the far side of the Sajo river, forced the Hungarians to retreat into their wagon laager camp, a traditional tool of fighting against nomadic armies. However, the Mongols surrounded the fortified Hungarian camp, and bombarded it with trebuchets, gunpowder weapons, and flaming arrows. Hungarian cavalry charges were lured further away from their camp and encircled. The result was complete panic; and to ensure that the Hungarians did not fight to the last man, the
Mongols left an obvious gap in their encirclement. This was one of Subutai's classic tricks, to create a tactical situation which appeared to be favourable to the enemy. Subutai did not want a battle where the massed crossbowmen, supported by mounted knights, stood firm and fought to the death against his army. He far preferred to let them flee and be slaughtered individually. The apparent gap in the Mongol lines was an invitation to retreat, which would leave the knights and crossbowmen spread out all over the countryside, easy pickings for the disciplined Mongols. As Subutai had planned, the Hungarians poured through this 'hole' in the Mongol lines, which led to a swampy area, poor footing for horses and hard going for infantry. When the Hungarian knights split up, the Mongol archers picked them off at will. It was later noted that corpses littered the countryside over the space of a two-day journey. Two archbishops and three bishops were killed at the Sajo, plus more than 10,000 fighting men. In one stroke, the bulk of Hungarian fighting men were totally destroyed, but Mongol casualties in the center had been higher than normal: in addition to anywhere from many hundreds to many thousands of regular soldiers, Batu lost 30 of his 4,000 strong
ba'aaturs (heavily armored bodyguards) and one of his lieutenants (Bagatu/Bakatu), which caused tension later in the camp.
Mongol subjugation of Hungary In addition to defeating the enemy, Subutai also had to spend substantial energy keeping the egos of the Mongol princes in check during the Hungarian campaign. During the battle, Subutai had to shame Batu into continuing the fight after the first failed attack on the bridge. Batu first blamed Subutai for taking too long to ford the river, but Subutai rebuffed him by saying that they knew fording the river would take time, and Batu had launched his attack preemptively. In the end Batu apologized to Subutai. Guyuk and Buri, jealous of Batu, accused Batu of incompetence and riding Subutai's coattails. This resulted in Guyuk and Batu, and possibly some of their men being sent home to Ögedei Khan for judgment, causing further rifts in the Mongol army. Despite these obstacles, the Mongols still attempted to solidify their control over Hungary. From Rogerius' writings it would seem that scattered resistance by the peasantry was attempted, but it never really got off the ground, perhaps in part due to the flat open plains of central Hungary allowing scant opportunity for ambush or withdrawal. After the defeat of the Hungarians at Mohi, Subutai used a stolen royal seal to issue bogus decrees across the country, leaving many unassuming inhabitants at his mercy. In order to keep the pressure on Bela, Subutai split his forces into several detachments. A light cavalry force under Kadan was sent to chase King Bela along the
Adriatic Coast, while the main army with its siege engines under Subutai and Batu attempted to pacify Hungary proper. Other Mongol forces raided outside the borders of Hungary, even reaching Austria before being repulsed in a skirmish near Wiener Neustadt. The Mongols successfully besieged several cities, including the fortified city at
Oradea, the castle of
St. Martin of
Pannonia, and the capital
Esztergom, though the latter's stone citadel held out, and not all sieges proved successful. By early 1242, Subutai was discussing plans to invade the
Holy Roman Empire, when news came of the death of
Ögedei Khan and a revolt by the Cumans in Russia. Carpini alleges that, over the objections of Subutai, the Mongol princes withdrew the army to Mongolia for the election of a new Great Khan. This account of events is disputed, with Rashid al-Din specifically noting that Batu and Subutai only heard of the Khan's death after they had already begun the withdrawal. However, the death of Ogedei and the turmoil immediately after it prevented the Mongols from returning to Europe for decades. Still, the devastation had been immense. Subutai had devastated the agriculture of any area that was resisting. Though some of the civilians had escaped capture or death by hiding in castles, forests, or marshes, they returned to their ruined fields only to starve. Some historians have claimed that a quarter to a half of Hungary's population may have died from the invasion. Even in 1250, eight years after the Mongols had left, Hungarian King Bela wrote to
Pope Innocent IV that Hungary could not withstand another invasion and would have to surrender to the Mongols if they returned. ==Final years==