He was the second son of King Christopher II of Denmark and Euphemia of Pomerania. His father and brother were deposed in 1326 and restored three years later on the condition his father signed a charter that gave him little to no power while the Danish nobles and the Counts of Holstein ruled behind the scene and mortgaged most of the kingdom.
Otto was given the titles Duke of Lolland and Estonia and was expected to expand the Danish conquest of Estonia acquired during Livonian Crusade. The Danish nobles for some reason decided not to elect a successor. He was held prisoner in the Segeberg Castle.
Upon his father"s death and his failed attempt to seize the throne, Denmark ceased being a formal kingdom, and for the next eight years it was subjected by various mortgagees to German military rule.
Once Valdemar became king in 1340, Otto was released on the condition that he surrender his claim to the throne. Otto subsequently went to Germany, and joined the Teutonic Order in 1346.
The Order bought his duchy in the same year, and no further information is recorded about him. Otto is the other (?Translation needed?) hero of Bernhard Severin Ingemann"s novel, Prins Otto af Danmark og Hans Samtid (Prince Otto of Denmark and his Time, 1835).
