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. However, in 1794, French revolutionary troops conquered Koblenz; in the following years they besieged Ehrenbreitstein three times without success. But a one-year siege, starting in 1798, brought starvation to the defenders of Ehrenbreitstein who finally handed over the fortress to French troops in 1799. By the treaty of Lunéville, the French were forced to withdraw from the right bank of the Rhine. Hence, they dismantled Ehrenbreitstein in 1801 to prevent the enemy from taking hold of a fully functional fortress just a few meters away from French territory on the left bank of the Rhine.
According to the Final Act of the Congress of Vienna in 1815, the Rhineland became a Prussian province. The fortification of the Koblenz area became a Prussian military priority, because of its proximity to France and the fact that Koblenz was a bottleneck for all means of transportation (ships, railways, land transportation because of bridges). Hence, the Prussians built a system of fortification around Koblenz, the so-called Fortress Koblenz, from 1817 until 1834. Yet, the name Fortress Koblenz should not be interpreted as if the whole city of Koblenz was a fortress. It should be rather viewed as a buzz word, referring to the ring of fortification around Koblenz, of which the Festung Ehrenbreitstein was a part. Fortress Koblenz was said to have been the largest military fortress in Europe except for Gibraltar. However, it is a common misconception, that the 'Festung Ehrenbreitstein' alone was the largest fortress in Europe. Ehrenbreitstein could be defended by up to 1200 soldiers. Unchallenged, it remained in service until 1890.
In 1822 the English translation of the castle's name, The Broad-Stone of Honour, was used as the title of Kenelm Henry Digby's exhaustive work on chivalry.
In 1897, a Monument to Emperor Wilhelm I was erected right below the Festung, but on the west side of the Rhine, known as the Deutsches Eck (German Corner). Both fortress and monument were considered as symbols for the 'Guard at the Rhine', as in the song 'Die Wacht am Rhein'.
During World War I the fortress was used as military headquarters. After World War I, the American General Henry Tureman Allen, convinced of its historical value as a premier 19th-century fortress, prevented its intended destruction. It was occupied by the US Army as their headquarters during the occupation of the Rhineland, and after January 1923 it was occupied by the French Army. During World War II, it served as a place of safekeeping for archives and cultural objects but also harbored three flak guns.
After World War II, it was used first by the French Army before it was handed over to the State of Rhineland-Palatinate. It now has multiple uses including a youth hostel, restaurant, museum and archive. In 2011, Festung Ehrenbreitstein will be part of the National Garden Show in Koblenz and is thus currently under renovation.References:
First record of Kastelholma (or Kastelholm) castle is from the year 1388 in the contract of Queen Margaret I of Denmark, where a large portion of the inheritance of Bo Jonsson Grip was given to the queen. The heyday of the castle was in the 15th and 16th centuries when it was administrated by Danish and Swedish kings and stewards of the realms. Kastelhoma was expanded and enhanced several times.
In the end of 16th century castle was owned by the previous queen Catherine Jagellon (Stenbock), an enemy of the King of Sweden Eric XIV. King Eric conquered Kastelholma in 1599 and all defending officers were taken to Turku and executed. The castle was damaged under the siege and it took 30 years to renovate it.
In 1634 Åland was joined with the County of Åbo and Björneborg and Kastelholma lost its administrative status.