Did the death of Ögedei save Europe from the Mongols?

The short answer

• The resources of a dynasty. The expedition that reached the Kalka in 1223 had roughly 20,000 riders. In 1236 Batu led a campaign backed by a kurultai decision and princes from all four family lines. Subötai brought experience of the earlier journey. A raid could expose routes and opponents; this time the dynasty committed resources for a conquest on a much larger scale.
• Winter made usable. Winter offered opportunities to an army prepared for its hardships. Frozen rivers led toward cities, hard ground could help movement, and horses could dig through snow for grass. Stores gathered after harvest offered another resource. The cold remained difficult for men and animals, but Mongol forces could campaign while opponents struggled to assemble across separate principalities.
• Opponents divided. The invasion encountered rival Rus rulers and a Poland divided among Piast dukes. Béla also sought help farther west, where Emperor Frederick II and the pope were in conflict with each other. Batu cited Hungary’s shelter of Qipchaq refugees in his ultimatum. These divisions made a common response hard to organize; no relief army reached Hungary.
• Refugees and the Hungarian defense. Qipchaqs fleeing the Mongols found refuge in Hungary. Batu treated them as subjects who had escaped Mongol authority and invoked their shelter in his demand to Béla. Inside Hungary, rumors turned people against the newcomers. Their khan Köten was murdered in Pest, and his followers departed, burning and fighting as they went. Shortly before Mohi, Hungary had lost experienced steppe cavalry that might have helped defend the kingdom.

What it changed

Rus under the Horde. The Rus principalities retained their princes and faiths, but the Horde required tribute, censuses and the khan’s approval for rule. This relationship endured in changing forms for roughly 240 years. Moscow, a small town on the map, later gained power partly by collecting tribute. Historians continue to debate how much Muscovite autocracy owed to Horde rule.

The withdrawal and its explanations. Ögedei died on 11 December 1241, leaving leading princes to consider their place in the succession. Batu’s rivalry with Güyük makes the political stakes plain, yet Batu did not attend the eventual kurultai. Another explanation begins in Hungary, where pasture and supplies had been damaged and large herds were difficult to feed. Succession may help explain when the armies left; environmental and strategic costs also help explain the limits of further campaigning. The evidence does not assign a certain share to either cause.

Europeans travel east. After the shock of 1241, Europeans sent travelers east to learn about the Mongols. Carpini went in 1245 and Rubruck in 1253, returning with accounts of Asia and its rulers; their route appears in Chapter 7. Later Horde raids struck borderlands, but an army on the same scale did not return. Succession struggles, the Berke–Hülegü war and Hungary’s new stone castles all belonged to the later setting. Survivors had reason to feel relief, even though historians still dispute why the invaders withdrew.