Two difficulties are met with in giving an account of the sources of German history. In the 7th, 8th and 9th centuries it is hard, if not impossible, to disentangle the history of Germany from that of the rest of the Frankish empire of which it formed part; in fact it is not until the time of the dissensions between the sons of the emperor Louis I. that there are any signs of demarcation between the East and the West Franks, or, in other words, any separate history of Germany. The second difficulty arises later and is due to the connexion of Germany with the Empire. Germany was always the great pillar of the imperial power; for several centuries it was the Empire in everything but in name, and yet its political history is often overshadowed by the glamour of events in Italy. While the chroniclers were recording the deeds of Frederick I. and of Frederick II. in the peninsula, the domestic history of Germany remained to a large extent unwritten. Among the early German chroniclers the Saxon Widukind, the author of the _Res gestae Saxonicae_, is worthy of mention. He was a monk of Corvey, and his work is the best authority for the early history of Saxony. Lambert, a monk of Hersfeld, and Widukind's countryman, Bruno, in his _De bello Saxonico_, tell the story of the great contest between the emperor Henry IV. and Pope Gregory VII., with special reference to the Saxon part of the struggle. But perhaps the ablest and the most serviceable of these early writers is Otto of Freising, a member of the Babenberg family. Otto was also related to the great house of Hohenstaufen, a relationship which gave him access to sources of information usually withheld from the ordinary monastic annalist, and his work is very valuable for the earlier part of the career of Frederick I. Something is learned, too, from biographies written by the monks, of which Einhard's _Vita Karoli Magni_ is the greatest and the best, and Wipo's life of the emperor Conrad II. is valuable, while another Carolingian courtier, Nithard, has a special interest as, almost alone among these early chroniclers, being a soldier and not a monk.