After conquering Eastern Europe and occupying Hungary for a year, Batu and his forces suddenly halted their advance and returned to the Eurasian steppes.
Several theories attempt to explain this move, including the "political theory" attributing it to Ögedei Khan's death, the "geographical or ecological theory" suggesting environmental difficulties, the "limited goals theory," and the "military weakness theory."
While each theory presents some evidence, they contradict one another on key points.The "ecological theory" suggests that Europe could not support the pasture requirements of the Mongol horses, but later research suggests that Hungary's pastures could have sustained more animals than initially estimated.
Moreover, evidence of a severe famine in Hungary during the invasion does not appear in Mongol sources, and the Mongols repeatedly demanded submission from European powers after their departure.
The "military weakness theory" is also dismissed as the Mongols won major clashes and sacked important cities. However, the Mongols experienced losses in battles against the Hungarians and Poles and faced difficulty conquering strategically situated stone castles. Batu Khan may have concluded that continuing the advance would overextend his forces.
Additionally, there are rumors that Mongol shamans forbade a return to Hungary due to bad omens. The reasons behind the Mongol departure from Europe remain unclear, and ongoing debates aim to shed light on this intriguing historical mystery.
