Wikipedia
The Ezzonids (, ) were a dynasty of Lotharingian stock dating back as far as the ninth century. They attained prominence only in the eleventh century, through marriage with the Ottonian dynasty of Holy Roman Emperors. Named after Ezzo, Count Palatine of Lotharingia from 1015 to 1034, they dominated the politics of the middle and lower Rhine and usually represented the royal interests. Under the Salian Emperors, they even briefly held the dukedoms of Swabia, Carinthia, and Bavaria.
The Ezzonids first appear with Erenfried I (866904), count of the Bliesgau, , and , and perhaps also of the Charmois. He may have had Carolingian ancestors, although some historians prefer to link him to the former Thuringian kings. The political ascent of the Ezzonid dynasty becomes historically visible with the number of counties they acquired in the second half of the tenth century. They ruled most of the Rhenish counties and were eventually granted Palatine status over the other counts of the district. In spite of their military accomplishments in the service of the Emperors, the Ezzonids did not succeed in building a territorial entity in Lotharingia.