Otto I, Margrave of Hachberg-Sausenberg

Margrave Otto I of Hachberg - Sausenberg (* 1302, † 1384 ) was the son of Margrave Rudolf I of Hachberg - Sausenberg and the heiress of Otto von Rötteln, Agnes (?). After his brother Henry had died in 1318, Otto took over with his second brother Rudolf the regency over the reigns Rötteln and Sausenberg. The residence was transferred from the Sausenburg the castle Rötteln. After his brother Rudolf II 's death ( 1352) he first took over the guardianship of his nephew Rudolf III. , Which he then in 1358 transferred to the Count of Thierstein. When Rudolf III. 1364 took his inheritance, he ruled jointly with his uncle until his death in 1384. Otto was married to his first marriage to Catherine of Grandson and his second wife, Elizabeth of Strassberg († 1352) and had no descendants.

In the fall of 1332, the besieged troops of the city of Basel Rötteln his castle because he had (or his brother ) stabbed the mayor of Basel. The dispute was settled by arbitration by the nobility of town and country.

The Margrave Hachberg - Sausenberg, Rudolf III. and Otto, the church donated to Sitzenkirch 1366 the altar of the Holy Cross. Margrave Otto was in 1384 buried in the church at Sitzenkirch.