Notker's more factual approach and alleged "recollection" was supposed to motivate (not intimidate) Charles the Fat by speaking of Charlemagne's feats, but not embellishing them. Although this book is compiled of two unique approaches to the life of Charlemagne, three common themes representative of this time period prevail: the political system of feudalism, the dual power of church and state, and the rebirth of culture in the Carolingian Renaissance.
The first major theme presented in The Two Lives of Charlemagne was the idea of feudalism. In this system, there was an Emperor at the top and a strict layout of positions under it. This command structure was based around the military hierarchy, which placed all the power in the hands of less than 10% of the population. Titles were awarded to those who "outshone all others by family distinction and the extent of their wealth" (56). The tradition was then carried through generations by the system of primogeniture, where the eldest son inherited the property of the family. Those families not privileged enough to be elite were expected to pay a "vassalage", or due to an authoritative figure. In return, the poor vassals looked to their lords and King to feed, clothe, house, and arm them. According to Einhard, "the King possessed nothing at all of his own, except a single estate with an extremely small revenue, in which he had his dwelling and from which came the servants, few enough in number, who ministered to his wants and did him honor" (55). The symbol of feudalism, a heavily armored knight, was defined by the subservient lower class that was constantly trying to move up in the ranks.
In accordance with the idea of feudalism was the dualism present in the powerful hierarchies of church and state. By the fusion of Roman and Germanic worlds with Christianity, Charlemagne built the largest territory since the fall of Western Rome, choosing the capital to be Aachen.