Interregnum (HRE)

There was no emperor of the Holy Roman Empire between 1245 and 1312, and again during 1378–1433 and 1437–1452. The crisis of government of the Holy Roman Empire and the German kingdom thus lasted throughout the late medieval period, and ended only with the rise of the House of Habsburg on the eve of the German Reformation and the Renaissance. The term Great Interregnum is occasionally used for this period, sometimes limited to the period of 1250 (death of Frederick II) and 1273 (accession of Rudolf I).

After the deposition of Frederick II by Pope Innocent IV in 1245, Henry Raspe, Landgrave of Thuringia was set up as anti-king to Frederick's son Conrad IV (d. 1254). Henry was killed in 1247 and succeeded as anti-king by William of Holland (died 1256). After 1257, the crown was contested between Richard of Cornwall, who was supported by the Guelph party, and Alfonso X of Castile, who was recognized by the Hohenstaufen party but never set foot on German soil. After Richard's death in 1273, Rudolf I of Germany, a minor pro-Staufen count, was elected. He was the first of the Habsburgs to hold a royal title, but he was never crowned emperor. After Rudolf's death in 1291, Adolf and Albert were two further weak kings who were never crowned emperor.

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