Olsberg

During the neolithic era there was a small settlement near Olsberg. There was also a Roman farm in the area during the 1st Century AD. The modern village of Olsberg is first mentioned in 1236 as Olsperg. The original settlement grew out from the courtyard of the convent. Until 1790, the convent held the low justice rights as well as the ownership of the land. With some interruptions, the part of Olsberg to the right of the Violenbach stream belonged to the Austrian district of Rheinfelden from 1330 until 1797. After 1797 it was a French protectorate and then went with the rest of the Fricktal to the newly formed Canton of Aargau in 1803. The left hand side of the stream belonged to the city of Basel from 1461 and later to Canton of Basel-Country .
The Abbey Church was renovated between 1670-1707. It was originally a branch church of the parish church in Kaiseraugst. After 1786 it became the parish church of its own parish. In 1872 it became the first Christian Catholic parish church in Switzerland.

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