Wikipedia
The Hattonids were an important imperial noble family in the first half of the 9th century, during the reigns of the Carolingian kings Charlemagne and Louis the Pious. They lost their position under Louis the German. They were patronised by the emperors and were enfeoffed with benefices on imperial estates. They attended empire-wide councils and were given military commands on the borders to defend the empire from Danish Vikings and Slavs.
Hailing from Saxony and Bavaria, where they had many lands and honores, the Hattonids were appointed to prefectures and counties in East Franconia and the central Rhineland from an early date. One of their family, Banzleib, was both Count of Maine in Neustria and Margrave of Saxony under Louis the Pious. The Hattonids more or less controlled Saxony in the last years of Louis the Pious' reign. They were staunch supporters of Louis the Pious and his eldest son Lothair I in the years from 838 to 843. They had a hatred for Louis the German and opposed his rule in Saxony and the creation of a kingdom of East Francia, since they had lands on both sides of the Rhine. Louis the German, however, jealous of their influence and power in the Rhineland, made war on them; a war which culminated in the Battle of Wörnitz, whereat the Hattonid leader Adalbert, Count of Metz, died. Adalbert and Banzleib's older brother, Hatto, was displaced from his county of Nassau, too, but he maintained his ground in Alemannia until at least 857.