Wenceslaus I of Bohemia

Wenceslaus I held Bohemia together through the Mongol invasion of 1241 by declining to fight it in the open. He was the son of Ottokar I and succeeded in 1230, inheriting a kingdom whose hereditary royal title was barely a generation old and whose nobility had to be managed rather than commanded. When the Mongol armies came west in 1241, the northern wing under Orda and Baidar drove through Poland, destroyed the Polish and German knights at Legnica, and turned towards Bohemia; the main force under Batu and Subutai was meanwhile annihilating the Hungarians at Mohi. Wenceslaus had gathered an army and was marching to join the Poles when Legnica was fought and lost without him - by a day or two, depending on the source. What he did next is why Bohemia survived: instead of seeking the battle that had destroyed everyone else who sought it, he garrisoned the fortified towns and monasteries, kept his field army intact and shadowing, and let the Mongols find nothing worth besieging. They passed through Moravia, burned what was open, and went south to Hungary. He spent the rest of the reign building exactly that capacity - stone castles, walled towns, German settlers invited into the silver-mining regions - which made Bohemia the strongest state in central Europe under his son. His last years were spent fighting that son, Ottokar II, who rebelled in 1248 and was defeated and reconciled. He died in 1253 hunting, and Ottokar succeeded him and took Austria within months. He was blind in one eye from a hunting accident and is called Wenceslaus the One-Eyed in some chronicles. His sister Agnes of Bohemia founded hospitals and was canonised seven centuries later. The German colonisation he encouraged reshaped the kingdom's economy and its language politics for the next six hundred years.

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