The castle in Bytów was built by the Teutonic Knights in 1398-1405. The major construction works were supervised by Nicolaus Fellensteyn, a master builder of the Order. The construction of the castle fell to the period when Jacob von Reinach was the procurator of Bytów and Konrad von Jungingen was the Order's Grand Master. The castle was located on a hill, towering above the town, which guaranteed excellent natural defence. The castle, very modern for those days, was a seat of the local administration officials, a border fort and a stopover for knights arriving from western Europe to Malbork. The seat of the Bytów procurator, the castle, most probably housed from a few to more than a dozen knights accompanied by their pages and lansquenets. The complete crew of the castle could count a few dozens.
During the Thirteen Years' War (1454-1466) Bytów Castle was ceded by the towns people of Gdańsk to the Polish King, Kazimierz Jagiellończyk. In 1454 it was granted by the King to the Duke of Pomerania, Eric II, whose family, the Gryfits, ruled the castle and the lands of Bytów until the death of the last member of the dynasty, Bogusław XIV. The castle, enlarged by the Gryfit dukes in the second half of the 16th century, became a seat of the local administration officials in the early 17th century and a summer residence of Pomeranian dukes. Around 1560 the castle court was redone and the construction of a new wing, known as the Ducal House, was undertaken. Once it had been completed, an identical, although smaller building was constructed adjacent to the curtain walls. This one was named the Ducal Chancery. Both exquisite buildings with imposing stairway towers turned the fortress into a Renaissance residence. In 1637-1657 the castle and the land of Bytów were administered by Polish officials. Badly damaged by Swedish troops in 1656, the castle and the lands of Lębork and Bytów were ceded, by the power of the Welawa-Bydgoszcz treaty, to Frederic Wilhelm I, Elector of Brandenburg. When the Brandenburgians arrived, they found the castle and the town, as well as many of the nearby villages damaged and looted by the Swedes in 1656. The Gunpowder Tower had been then blown up and most of the castle buildings burnt, leaving only the external walls. Despite many efforts, the castle has never been brought back to its previous magnificence.
The castle, which had also lost its earlier functions, was then used to house a court of justice and a treasury office. Some if the castle buildings were converted into apartments, some changed into storehouses and workshops. After 1930 the German state authorities designated the castle to serve as a training centre and a hostel for youths. The renovation and adaptation works which were then started stopped at the outbreak of World War Two. In the 1960s the renovation of the castle was resumed and eventually the east wing, which had been restored first, was opened in 1974, housing a new municipal public library. The south wing, where the Zamek Hotel and a restaurant are located, was opened in 1980. The north wing, renovated in 1991, provided room for the Museum of Western Kashubia. The Museum has 15 exhibition rooms on three storeys of the former Monastic House and on the two topmost floors of the Mill Tower. The permanent exhibitions show examples of material culture of the Kashubians and collections of art objects and historical mementos, including some relics of the interior design of St George church in Bytów, portraits of dukes of Pomerania, armoury and weaponry. The last floor of the Mill Tower contains an exhibition which documents the history of Bytów castle and its reconstruction.
References:Doune Castle was originally built in the thirteenth century, then probably damaged in the Scottish Wars of Independence, before being rebuilt in its present form in the late 14th century by Robert Stewart, Duke of Albany (c. 1340–1420), the son of King Robert II of Scots, and Regent of Scotland from 1388 until his death. Duke Robert"s stronghold has survived relatively unchanged and complete, and the whole castle was traditionally thought of as the result of a single period of construction at this time. The castle passed to the crown in 1425, when Albany"s son was executed, and was used as a royal hunting lodge and dower house.
In the later 16th century, Doune became the property of the Earls of Moray. The castle saw military action during the Wars of the Three Kingdoms and Glencairn"s rising in the mid-17th century, and during the Jacobite risings of the late 17th century and 18th century.