Much like other Leaders in the past, none who came after Charlemagne could achieve what he had.
Except for Charles the Fat, Otto the Great, maybe Frederick Barbarossa, etc...
Is their a way to continue the path of education, standard coinage, unified cultures, and the continuing progression of medieval Latin to a unified language amongst his territories.
First: there were
no unified cultures in this period. There was no "German" identity, no "French" identity, etc. The closest possibility is the Italians, who may remember vaguely having been Romans at some point long ago.
The cultures were more along the lines of: Aquitainian, Neustrian, Burgundian (
Provençal), Frisian, Saxon, Alemannian, Bavarian, Lombard, etc. Local identities. Even more, people considered themselves first and foremost a member of their home town. IE: a Neustrian from Paris would consider himself first a Parisian, then a Neustrian.
However, this
was accompanied by an overarching sense of "Frankish-ness" (for want of a better word). Everyone in Francia saw themselves as a Frank, albeit after everything else. So that guy from Paris I mentioned, living in the ninth century, would perceive himself thus: a Parisian, a Neustrian, and a Frank. So I suppose in a sense there was some sort of universal culture, but it did not overtake or assimilate other cultures. It's kind of like considering oneself an American at the same time as being Irish or German or whatever.
BTW, I was unaware as to the centralizing of Latin in this period. Any sources on that?
Well, I think Louis the Pious was a pretty good leader. The obvious problem is that you have to keep some sort of non-division, but the question is; how do you establish actual primogeniture?
Adoption instead, perhaps?
I don't know how well this would work though. The Carolingian Empire was
built around division of the empire. With a caveat, however: whenever the empire was divided, the heirs were given the title of king
at best, with the tacit understanding that the empire would eventually be reunited under one of them. So when Louis divided Francia between his sons, the three knew - or hoped - that they would be the one to restore the realm and become sole Emperor.
As paradoxical as it may seem, the empire stayed together by dividing. Younger sons were given lesser kingdoms - like Pepin I getting Aquitaine, Bernard getting Italy in 810, Louis the German granting Carloman Bavaria, Charles the Bald giving Aquitaine to his son Charles the Child, etc - to bring stability. Local nobles could be placated by a local king who could interact with them on a regular basis. He could grant
honores, administer the kingdom, dispense justice, and do
other functions as well. The local sub-king would in turn answer personally to his father or relative serving as Emperor. If the empire were forced to remain whole, the nobles would be more likely to become disenfranchised after a while - although at first I think the system would hold.
Case in point: Charles the Fat's reign in Alemannia / Swabia. Probably the pinnical of the Carolingian system: a popular, local king governing personally and supporting the Church, enjoying full support of the nobility. In a few short years this system made Alemannia into a hub of Francia.
There was a good bit of conflict about the royal vs. imperial succession, but it was always clear that only one could be emperor. If Charlemagne could somehow ensure that the military resources of the empire were available to the emperor, that would be immensely helpful. One idea would be the concept that only the heartland is divisible by Frankish custom, so the sons of the king-emperor get a share of Neustria and Austrasia, but Aquitaine, Saxony, Thuringia, Bavaria and the Lombard kingdom stay in the hands of the emperor only.
A few problems with that idea: Charlemagne was one of the most enthusiastic proponents of division. He gave kingdoms to each of his three sons.
But more importantly, that division doesn't make much sense. Neustria was a backwater that nobody wanted - the only post-Charlemagne king of Neustria was Louis III of France, who ruled for five years. Aquitaine and Bavaria were
the prizes, the two kingdoms that everyone fought over and bent over backwards in attempts to obtain. Italy and Lotharingia were valuable as well. Having Italy, Aquitaine, and Bavaria unable to be divided would only lead to civil war and breakdown of the empire (more rapdily than OTL).
The Imperialists win the
Battle of Fontenay and thus the stage is set for a centralization of the Empire.
OK, a bit wishful thinking, but hey, why not?
That is actually an interesting idea. Best-case scenario that I can see for Lothair is that he kills or exiles Louis and Charles, keeping the empire for himself. When he dies in the 850s - roughly as in OTL - he divides the empire between his three sons. Louis, the eldest son (OTL Louis II of Italy), gets Middle Francia, Lothair II gets East Francia, and Charles (OTL Charles of Provence) gets Aquitaine and later West Francia. So it's basically Louis the Pious all over again.