The building history of the first Rheineck Castle, which appeared shortly before 1115, is by and large unknown. The sources name the count palatine Otto I of Salm as the founder. After his death, King Konrad III seized his estate and transferred it to his brother-in-law, Count Herman of Stahleck. This endeavour resulted in a bitter fight for the County Palatine of the Rhine - a conflict that culminated in the complete destruction of Rheineck Castle by the troops of the King in 1151. Rheineck Castle was rebuilt by the Archbishopric of Cologne by 1164 at the latest but did not, however, withstand the Palatine War of Succession in the 17th century. The Prussian politician von Bethmann-Hollweg inherited the ruin in 1832 and had the main building reconstructed together with the castle chapel. The latter represents a special feature, with its eight-sided design, which is reminiscent of the Carolingian Octagon of Aachen Cathedral. Today, the Castle is in private ownership and cannot be visited.