Amriswil is a municipality in Arbon District in the canton of Thurgau in Switzerland.Amriswil is first mentioned in 799 as Amalgeriswilare. During the Middle Ages Amriswil and Brüschwil were part of a Bishop's fief. During the 15th Century, the Helmsdorf family ruled in Eppishausen. In the early 17th Century, the village of Amriswil was sold to Adam Tschudi of Glarus, and in 1665 the hospital was sold to St. Gallen.
The court rights over Amriswil, Hölzli, Brüschwil and houses in Ruti and Giezenhaus were acquired by the city of Bürglen, which was under the control of the city of St. Gallen. This situation remained unchanged until 1798.