 After the division of the Frankish Empire, East Francia ("Francia orientialis") was formed from the territories of the dioceses of Mainz, Worms, Würzburg and Speyer.Later, the diocese of Bamberg was added.In the 7th century, the Slavs started to populate the northeastern parts of the region from the east, because the area of today's Upper Franconia was very sparsely populated (Bavaria Slavica).