Arnstein Abbey is a former Premonstratensian abbey on the Lahn River. The history of the monastery dates back to the second half of the 11th century. In 1052, an Arnstein Castle on the Lahn is first mentioned as the seat of the Counts of Arnstein. This is the oldest mention of any castle on the river. Nothing remains of the structures of that period.
In 1139 Louis (Ludwig) III, the last Count of Arnstein, transformed his castle into a Premonstratensian monastery and himself joined the order. His wife lived until her death as hermit near the monastery. In the same year, Lugwig began the partial demolition of the castle. In 1145, King Conrad III confirmed the abbey as directly under the Empire. From 1236, a branch monastery, Keppel Abbey at Hilchenbach, was established under the patronage of the House of Nassau.
Burials in the monastery include Count Walram I of Nassau in 1198. Walram's grandson Henry (Heinrich) (son of Count Henry II of Nassau) became a monk in Arnstein Abbey in 1247.
In 1360, the monastery church was completed. The structure includes individual components which have been dated to the 12th century.
In 1803, the monastery was dissolved during secularization and came into the possession of the Principality of Nassau-Weilburg. In 1919 the Congregation of the Sacred Hearts of Jesus and Mary established Arnstein as their first monastery in Germany. The Superior and Vice-Provincial of the monastery, Pater Alfons Spix, died in 1942 in the Dachau concentration camp, because he let the Polish forced laborers participate in worship and gave them breakfast.
References:Ehrenbreitstein Fortress was built as the backbone of the regional fortification system, Festung Koblenz, by Prussia between 1817 and 1832 and guarded the middle Rhine region, an area that had been invaded by French troops repeatedly before. The fortress was never attacked.
Early fortifications at the site can be dated back to about 1000 BC. At about AD 1000 Ehrenbert erected a castle. The Archbishops of Trier expanded it with a supporting castle Burg Helferstein and guarded the Holy Tunic in it from 1657 to 1794. Successive Archbishops used the castle's strategic importance to barter between contending powers; thus in 1672 at the outset of war between France and Germany the Archbishop refused requests both from the envoys of Louis XIV and from Brandenburg's Ambassador, Christoph Caspar von Blumenthal, to permit the passage of troops across the Rhine.