Otto III of Hachberg

Otto III of Hachberg was Bishop of Constance from 1410 to 1434. During this time he was the host of the Council of Constance (1414–1418). Although he was the second person named Otto in the Hachberg-Sausenberg line of the House of Zähringen, he is consistently called Otto III in the literature, because he was the third bishop of Constance named Otto.