Located within the former Duchy of Swabia, the princely abbey was the second largest ecclesiastical principality of the Swabian Circle by area, after the Prince-Bishopric of Augsburg.

It stretched along the Iller River in the Allgäu region, from Waltenhofen (Martinszell) in the south to Legau and Grönenbach in the northwest, and up to Ronsberg and Unterthingau in the east.

[3] The abbey had financial and political support from the ruling Carolingian dynasty, mainly from Hildegard, the second wife of Charlemagne, and her son Louis the Pious.

By a privilege granted by King Rudolph I, the town of Kempten had freed itself from the authority of the abbot and became a Free imperial city, starting a long rivalry.

In 1775 the abbey ordered the last witchcraft trial in the Holy Roman Empire,[5] when Anna Maria Schwegelin was sentenced to death by decapitation, though the verdict was not enforced.