Sonvilier is a municipality in the Jura bernois administrative district in the canton of Bern in Switzerland. It is located in the French-speaking Bernese Jura (Jura Bernois). History Sonvilier is first mentioned in 1298 as Sunuilier. In 1307 it was mentioned as Sonvelier. Erguel Castle, now in ruins, was built south-east of the village in the 11th century. The castle was the center of government for the lands that the Lords of Arguel (or Erguel) ruled. In 1264 Otto von Erguel, who at the time lived in Basel, ceded the lands to the Prince-Bishop of Basel. In return the bishop granted him lands in Alsace. Under the Prince-Bishop the Erguel lands, including Sonvilier, became part of the seigniory of Erguel. During the 13th and 14th century a local noble family was mentioned in Sonvilier. During the 16th century the municipality was the largest in the Erguel and was home to a half dozen mills that were held in fief to the Prince-Bishop of Basel. After the 1797 French victory and the Treaty of Campo Formio, Sonvilier became part of the French Département of Mont-Terrible. Three years later, in 1800 it became part of the Département of Haut-Rhin. After Napoleon's defeat and the Congress of Vienna, Sonvilier was assigned to the Canton of Bern in 1815. Two social movements of the 19th century originated in Sonvilier. In 1843 Fritz Marchand founded the philanthropist L'Union Society. Nearly three decades later, in 1871, a chapter of the Fédération jurassienne (Jura Federation), a federalist and anarchist section of the International Workingmen's Association, was formed in the village. The Jura Federation leader, Mikhail Bakunin, held three conferences in the village during 1871. Religiously it was part of the parish of Saint-Imier. A Reformed parish church was built in the village in 1832. A Mennonite chapel was built in La Chaux-d'Abel in 1905. During the 18th and 19th centuries the local economy grew with small scale home work watchmaking and lace making. A number of small workshops provided watch parts for final assembly in other towns in the region. The financial crises of the 1930s and 1970s hit the watch making industry hard and many workshops went out of business. In 2005, only 9% of the jobs in the municipality are in manufacturing, while almost half are in agriculture. In 1874 the completion of the Biel-Les Convers railroad connected Sonvilier into the national rail network. In