The lords of Aarwangen were first mentioned between 1194 and 1212 as a Ministerialis (unfree knights in the service of a feudal overlord) family in service to the Kyburgs. Starting in 1266, Walter of Aarwangen was in the service of the future King of the Romans Rudolph I. Initially they owned land in the Emmental, but in 1276 they sold the land to Trub monastery. Around 1300 they built the tower of Aarwangen Castle along the banks of the Aar river. In 1313, they were firmly established in Aarwangen when Rudolf III of Neuenburg-Nidau granted them the bridge over the Aar river as a fief. After Walter's death in 1320, his son Johann took over the castle and leadership of the family. Johann was a patron of the Cistercian Abbey of St. Urban in Hasle, Lucerne and in 1341 he joined the Abbey. He remained at the Abbey until his death in 1350, which ended the Aarwangen noble line.
After the Aarwangen family died out, the castle went to the Grünenberg family. They sold it in 1432 to the city of Bern. It served as the seat of the Bernese bailiff until 1798. It is now the administrative seat of the surrounding district.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.