Career
He constructed Rheineck Castle and from c. 1124, he styled himself Otto of Rheineck, after his castle. However, King Conrad III of Germany, who had been elected in 1138, decided that the County Palatine was a completed fief, and hence fell back to the King, who gave it to his brother-in-law and devoted supporter Herman of Stahleck. Otto managed to keep Treis Castle until 1148, and Rheineck Castle until 1151.
In 1148, war broke out between Otto and the Emperor.
The Emperor took Treis Castle in 1148, and gave it to the Elector of Trier. In 1151, he captured and destroyed Rheineck Castle.
Otto Married Gertrude of Nordheim, daughter of Henry, Margrave of Frisia. They had several children, including:
Otto II (c 1115 – 1148/1149), fought against Herman of Stahleck to recapture the County Palatine of the Rhine and was taken prisoner in 1148.
He was later strangled at Schönburg Castle, near Oberwesel in 1148 or 1149
Sophia, married Dirk VI, Count of Holland (d 6 August 1157)
Beatrix, married Wilbrand I, Margrave of Frisia.