Saaremaa Island was conquered by the Crusaders in 1227, but in the following years numerous pagan uprisings broke out. It was not until five years after the uprising of 1260, that the Teutonic Order began the construction of the first fortifications in place of the later castle. It received its final architectural form only in the years 1330-1360. The castle was not the seat of a teutonic convent, but the property of the bishop. The end of its medieval history followed the fall and secularization of the Ösel–Wiek bishopric in the second half of the 16th century. The Livonian War, which caused enormous damage to the continental part of Estonia, did not fortunately affect fortress, which along with the island was sold to Denmark. In 1645, the Danes were replaced by the Swedes, and after 1710 the castle belonged to the Russians. Throughout this period, up to the beginning of the 19th century, Arensburg as the capital of the island and region, kept its military significance, and its fortifications were modernized. Fortunately, these extensions did not involve dismantling older, medieval fortifications. The first conservation work was carried out in 1904-1912, and a large-scale renovation took place in 1968-1985.
The oldest castle layout consisted of a single perimeter of the walls, reinforced with a single main tower. At the end of the fourteenth century, the stronghold was already a fully developed conventual castle, consisting of a regular, square inner ward to which wings adjoined from four sides. In the north-west corner there was the Sturwalt Tower, and in the north-east corner the slender and higher tower called Long Herman. The location of the latter was interestingly solved, because as the last point of defense it was separated by a free space in which the sewage from the latrines placed next to the guest chambers probably flowed. In the lowest storey Long Herman housed a prison dungeon. Inside the Sturwalt Tower had six floors, the two lower floors were covered with vaults and were connected by staircases, which started at a certain height above the floor, which made it easier to cut off the enemy’s access in case of danger. The upper floors had residential functions and were heated with fireplaces.
Like other Teutonic castles, the most important rooms were on the first floor, and the communication between them was provided by a stone cloister, built due to low temperatures. Its interior was covered with a cross vault with ribs embedded directly into the walls (a feature characteristic of the 15th century). The entire west wing was occupied by a bishop’s chambers with latrine, most of the southern wing was occupied by a large representative refectory with two aisles, and in the east range was a dormitory and a smaller refectory. In the corner of the southern range, there was a square chapel with a ribbed vault based on a central pillar with an octagonal cross-section. The castle did not have a chapter house, the meetings were most likely held in the southern refectory at a round table that was placed there. Before entering it, an element known from monasteries was used, namely a stone lavatory built into the wall, in which hands were washed before meals. An unusual architectural solution was the bishop’s alcove in the west wing, surrounded by an extremely thick wall without windows, a likely place of final shelter. Moreover, the entrances to the bishop’s chambers in the west wing could be blocked with bolts attached to the door.
The utility rooms were on the ground floor, and the third, upper floor had defensive functions. In the east wing, right under the smaller refectory and guest room, there were kitchens and a small brewery, there was also a small room with a well necessary for the daily functioning of the castle’s inhabitants. On the ground floor of the southern wing, apart from storage rooms, there were two chambers with hypocaustum furnaces. They provided heating for the episcopal chambers on the first floor, with the use of hot air transmitted through channels in the thickness of the walls and finding an outlets in the openings in the floors, closed with flaps if necessary.
The main building of the castle was surrounded by a hydrated moat, along which a small outer wall ran from the inside, giving the area of zwinger. Around the moat there was an outer bailey, also surrounded by a moat and fortifications. Originally it was a wooden – earth fortifications, which was replaced at the turn of the 14th and 15th century by a stone wall of 687 meters long and 7 meters high. The last medieval extensions took place in the mid-fifteenth century, when the external wall was raised and equipped with towers.
Arensburg is the best preserved medieval castle of the entire east coast of the Baltic Sea. Despite the damages and modern reconstructions of the north-western tower and vaults of the cloisters, the basic shape and most of the castle rooms, along with the gothic vaults and numerous architectural details, have survived. In the castle there is the Saaremaa museum, and the spacious area in front of the monument is the place of various outdoor events.
Borowski T, Miasta, zamki i klasztory, Inflanty, Warszawa 2010.
Tuulse A., Die Burgen in Estland und Lettland, Dorpat 1942.
Zamki regionu Morza Bałtyckiego, red. T.Kjaergaard, Bydgoszcz 1995.