Spiegelberg

Spiegelberg ruins stand above Le Noirmont, Switzerland; they were erected in the 13th century by medieval feudal builders, most likely Conon de Pleujouse.

Construction and early ownership in the 13th and early 14th centuries established the site as a noble residence. By 1315 the castle served as the seat of the Mireval family, first recorded with Conon (Cuenin) de Mireval, who died in 1320. Around that time the property passed into the hands of the Prince-Bishopric of Basel, an ecclesiastical principality whose authority over the Franches-Montagnes plateau reportedly dated back to a royal gift about 999. A settlement grew beneath the stronghold, with the village of Muriaux forming around 1300.

From the 14th century the lords of Spiegelberg acted as the Prince-Bishopric’s bailiffs, administering the lordship from the castle. In 1382 Bishop Jean III de Vienne placed the fortress as a pledge with his cousin, Admiral Jean de Vienne. Two years later Bishop Imer von Ramstein pledged the site, together with Porrentruy and Chauvilliers, for 4,000 gulden to the Council of Basel in order to free the admiral’s encumbrance. In 1388 Bishop Imer again pledged the castle and its lordship for 7,500 francs to Thiebaut VIII of Neuchâtel-en-Bourgogne. Subsequent disputes, involving later bishops including Humbrecht and Johann IV von Fleckenstein and episodes of armed occupation between 1424 and 1426, left final control with the bishopric while Thiebaut received financial compensation.

The lords of Spiegelberg eventually relocated to Solothurn in the 15th century; their male line ended in 1541. Spiegelberg remained under the Prince-Bishopric’s ownership until 1792. From the 14th into the 17th century the castle housed the Landvogt who administered the Freiberge region, until the office was transferred after later events.

In 1636, amid the Thirty Years’ War, Swedish forces attacked and occupied the castle and it later fell into the hands of French troops. The building suffered such severe damage that it was abandoned and left to decay, and the Landvogt’s seat was moved to Saignelégier. During the upheavals of the French Revolution, inhabitants from Le Noirmont, Muriaux and Saignelégier demolished remaining parts of the ruin with the declared aim to destroy every trace of tyranny. Over time visitors removed further masonry and cast it down the slope, accelerating the site’s ruin.

Observers around 1840 recorded the surviving fragments, noting a square tower and another structure roughly twenty metres long and five to six metres wide, and they described former approaches by wooden footbridges spanning cuts in the ridge. Near the turn of the nineteenth to twentieth century the parish priest of Le Noirmont led efforts to protect the remains: a path was laid, some walls were consolidated, and dangerous places were made safe with iron railings.