Rudolf I (1218-1291); also kown as Rudolf of Habsburg; was the son of Count Albert IV of Habsburg; and became count after his father's death in 1239. His godfather was Emperor Frederick II; to whom he paid frequent court visits. Rudolf ended the Great Interregnum that had engulfed the Holy Roman Empire after the death of Frederick when he was elected as King of Germany in 1273.

Rudolf secured the recognition of the Pope by promising to launch a new crusade and renouncing all imperial rights to Rome; the papal territories and Sicily. His main opponent was King Ottokar II of Bohemia; who had refused to acknowledge Rudolf as King of Germany. War was declared against Ottokar in 1276; and he was defeated and killed in 1278 during the Battle on the Marchfeld.

Rudolf was ultimately not entirely successful in restoring internal peace throughout the Holy Roman Empire; lacking the power; resources and determination to truly enforce his established land peaces; with the princes largely left to their own devices. He died in 1291; establishing the powerful Habsburg dynasty but unable to ensure the succession of his son Albert as German king.