Aarwangen Castle is a castle in the municipality of Aarwangen of the canton of Bern in Switzerland. It is a Swiss heritage site of national significance.HistoryThe 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.