Diessenhofen is a village and a municipality in Frauenfeld District in the canton of Thurgau in Switzerland. The village is situated on the south shore of the High Rhine just opposite the German town of Gailingen am Hochrhein. History Diessenhofen is first mentioned in 757 as Deozincova. In 2000, the village of Willisdorf was incorporated into the municipality. The earliest traces of a settlement are Stone and Bronze Age scattered objects found in the shallow valleys of the district and on the banks of the Rhine. A hoard of coins from the Roman era (251-270), and the remains of three towers of the Danube-Iller-Rhein limes (4th century) show Roman settlements in the area. The reference in a deed of the Abbey of St. Gall from 757 mention an Alamanni village, which was probably on the plateau south of the church. In 1178 Count Hartmann III of Kyburg, raised the village to town and probably appointed a Ministerialis (unfree knights in the service of a feudal overlord) family as the Stewards of Diessenhofen. By 1245, at the latest, it was the center of a bailiwick and a castle was built in town. Compared to Schaffhausen and Stein am Rhein, Diessenhofen was a modest market town. Hartmann granted the town a measure of freedom and self-government. He used the castle and bridge over the Rhine to secure and defend his possessions on both sides of the Rhine. After the extinction of the Kyburgs and the transition of sovereignty to the Habsburgs in 1264, the city developed as one of the cornerstones of the region. The Stewards, who sat at Unterhof Castle, temporarily united both the Vogt and Schultheiss offices into a single person. By 1320 the citizens chose a Town Council of 8-12 members, and during the 15th Century this evolved into a 24-28 member Grand Town Council. In 1349, the Duke of Austria wrestled the Vogt office away from the Stewards and granted it to another Ministerialis. These two developments made citizenship rights in Diessenhofen increasingly important. The loss of Habsburg influence and the decline of the Habsburg supported Stewards gradually transformed the city between 1415 and 1442. Diessenhofen was captured in 1460 during the conquest of Thurgau by the Swiss Confederation. The town was besieged for ten days before it was captured, but, much like Frauenfeld, it retained certain privileges in the new Thurgau. These included both the high and