The castle is first mentioned in 1219 as in arce Clanx,[1] named after the Sax family holding in the Calanca valley.

During a contested election for Abbot of St. Gall in 1272, Ulrich von Güttingen received support from the Habsburgs in exchange for a promise to take the castle and lands away from the Sax family.

Two years later, in 1274, Heinrich III was forced out and the Habsburg knight Ulrich von Ramschwag was given the castle.

In the following year a combined army from Appenzell and the city of St. Gallen attacked and captured Clanx.

After the Appenzell Wars, the Abbey retained control over the ruined castle and the hill on which it stood.