House of Frohburg

The House of Frohburg (also Froburg) was a noble family in medieval Switzerland, with possessions in what is now the canton of Solothurn.

They ruled the lands between Olten and Solothurn, and took parts of Aargau and Sisgau as fief from the bishop of Basel.

They reached the peak of their power in the later 12th and early 13th century, building a number of castles, and founding towns such as Aarburg, Liestal, Olten (then a fortified river crossing), Waldenburg, Wiedlisbach and Zofingen.

The Waldenburg branch survived for another 40 years but declined in influence, being forced to sell most of its possessions, most of them to the ascending House of Habsburg.

Herman III founded the Waldenburg branch, with lands in the canton of Basel.