Between 1206 and 1279, the Mongol Empire conquered every major civilization between the Pacific and the Danube. The Jin dynasty. The Khwarazmian Empire. The Russian principalities. The Abbasid Caliphate. The Song dynasty. At each step, the pattern repeated: destroy the field army, take the capital, collapse the state. The Mongols assembled the practical knowledge of every civilization they absorbed — Chinese siege engines, Persian engineering, gunpowder weapons — and deployed it against the next target. In 1241, they entered Europe. At Legnica they destroyed a combined Polish-German force. At Mohi they annihilated the Hungarian army. The Hungarian kingdom, with only ten stone castles, was the most steppe-adjacent state in Latin Christendom — the one European polity most similar to the kinds of targets the Mongols had already conquered. And then the Mongols withdrew. Hungary survived. The kingdom rebuilt. When the Mongols returned in 1285, Hungary repelled them. The standard narrative treats this as a near-miss: Europe was saved by the death of Ögedei Khan in December 1241, which forced the Mongol princes to return east for the succession election. Europe escaped by luck. Had the Khan lived, the narrative implies, the Mongols would have overrun the continent. The model predicts a different explanation. If Europe's multi-centre topology had been generating institutional innovation since the fall of Rome — if Nₑff was high, Cₘ was low, and M was growing — then Europe should have been structurally resilient against steppe conquest, regardless of who died when. The Mongol invasion of Europe is a direct test of whether European Iᵢnst was already elevated before 1492. The outcome of that test is unambiguous.
Yisheng WANG (2026) studied this question.