[1] In 1213, Holy Roman Emperor Frederick II declared the abbots of Kempten Abbey members of the Imperial Diet and granted the abbot the right to bear the title of Duke, making the abbey the Imperial Ducal Abbey of Kempten.

In 1289, King Rudolf of Habsburg granted special privileges to the settlement in the river valley, making it an Imperial City.

The Imperial City converted to Protestantism in direct opposition to the Catholic monastery in 1527, signing the Augsburg Confession.

During the turmoil of the Thirty Years' War (1632–33), the city was destroyed by imperial forces.

In 1819, the city was united with the properties of the Abbey into a single communal entity.