Two fairly well-known facts about Carolingian politics in the ninth century seem to have an obvious connection. Firstly, the century was marked by an interminable series of conflicts between Carolingian rulers of a divided Frankish empire. Secondly, the period saw a larger amount of political propaganda produced than in previous ages, in a variety of genres including contemporary history, biographies, letters and mirrors for princes. A number of studies have been produced showing how such political propaganda was one of the weapons used by Carolingian rulers in their internal conflicts. (Im currently reading Nicholas Staubach, Das Herrscherbild Karls des Kahlen: Formen und Funktionen monarchischer Repräsentation im früheren Mittelalter (1981), but there are lots of similar works).
My purpose today isnt to add to these studies. What I want to do instead is look at the causation the other way: to what extent did these works of propaganda actually contribute to extending these internal conflicts? I want to start with what I see as the key period for the development of such new forms of Carolingian propaganda: Louis the Pious reign between 814 and 822.
Carolingian propaganda wasnt new in the reign of Louis the Pious: Rosamond McKitterick in particular has written extensively on eighth century history writing as court-sponsored propaganda. And the individual blackening of enemies names also wasnt new to the ninth century, as Tassilo and Pippin the Retrospective Hunchback could testify. But Louis actions in 814, when he ascended to the throne, seem different. He looks to have been deliberately positioning himself as a better ruler than another Carolingian on the grounds of his closer adherence to Christian norms. The fact that this alternative Carolingian ruler was actually his own dead father Charlemagne shouldnt conceal the fact that Louis self-representation was a new pattern that would be repeated time and time again in the generations following.
If Louis in 814 showed the advantages of holier than thou propaganda, the events of 818 and 822 proved there was a downside. In 818 Louis blinded his rebellious nephew Bernard of Italy, who died as a result. In 822 Louis did penance for this act at the assembly of Attigny.
Mayke de Jong has argued repeatedly that this act was not a humiliation for Louis (and will presumably say more on the topic in her forthcoming book). But it did still make clear one definite limit on self-promoting Christian kings: they could not kill or main their relatives. This prohibition seems largely to have held: no legitimate Carolingian were killed in battle or executed after 817 (though a few illegitimate sons were). Only Charles the Balds son Carloman was blinded (in 873) and this was seen as particularly severe treatment.
Such a limitation does much to account for the prolonged conflicts between Carolingian rulers in the ninth century: it was almost impossible to being a definitive end to a conflict if none of the key players could ever be violently eliminated. The only option remaining was to confine ones opponent to a monastery. Such confinement had been used successfully as a punishment by Charlemagne (for both Tassilo and Charlemagnes own son Pippin). But once such incarceration had become the harshest possible penalty and the lurking threat of execution as an alternative had been effectively removed, there was every incentive for Carolingians to attempt to escape from such confinement (and for supporters to attempt to free them). From 830 onwards, the monastery became effectively a revolving door for Carolingians.
The characteristic internal campaign between Carolingian rulers and would-be rulers thus became a series of political and military manoeuvres punctuated with occasional all-out warfare. The aim was to win over an opponents supporters, by a combination of bribes and propaganda, in the hope that they might lose sufficient support to be captured or deposed or at least be willing to negotiate. Outright attacks had to be justified by the claim that they were unavoidable and had been provoked by the tyranny or other wickedness of ones rival. The ruthless persistence of Charlemagnes attacks was no longer possible in such a world; even the traumatic battle of Fontenoy in 841 was not decisive, and probably could not have been, unless one of the kings involved had accidentally been slain.
The limitations that Carolingian Christian kingship put on violence were not onerous by modern standards: magnates still got killed in battle and executed at other times, and the first non-Carolingian pretender to the throne, Boso of Provence, got dealt with effectively by Carolingians actually working together. But Christian kingship also brought another limitation: Carolingian rulers couldnt be too ruthless towards their bishops. Louis the Germans invasion of West Francia in 858 is the clearest example of this. Hincmar of Rheimss role in resisting Louis is well-known. In response to Louis demand for the bishops to come and advise him, at a time when Charles the Bald had lost most of his support among the lay magnates, Hincmar organised the sending of the Quierzy letter by the bishops in which they refused to attend Louis and reproached him for the invasion. Hincmars loyalty to Charles has often been noted, but no-one, as far as I know, has asked the question: why didnt Louis then respond by seizing Hincmar and killing or threatening him?
My suggestion is that while such a response would have seemed tolerable in some eras (Merovingian bishops got slaughtered with some regularity), a would-be exemplary Christian like Louis couldnt give Hincmar the once-over, however politically useful it would have been. Because such violence was off the table for Louis, it was easier for Hincmar and the other bishops to resist him. This in turn meant that Louis couldnt get the legitimation as ruler of West Francia he needed to maintain his temporary success over Charles the Bald. So once Charles regrouped his forces, Louis had to retreat and the situation was largely back to square one.
These limits on what was acceptable for Carolingians to do to each other also explain another feature of the conflicts in the ninth century: sudden bursts of intense action against ones opponent after a number of years of peace. If most attacks were unlikely to be successful (and a failed attack was potentially harmful to ones image as a peaceful ruler), it was important to seize any favourable opportunities that were going. This explains why there was such excitement when a rival king died (or looked near to death, as with Charles the Fat), and why Charles the Balds response to any family bereavement, in particular, was normally an invasion. Here at last, was an occasion when a rival was permanently eliminated: such rare events must be taken full advantage of.
It is these limits of the politically acceptable, I would argue, that ultimately give Carolingian relations in ninth-century Francia their distinctive flavour. This is not an era of the persistent low-level feuding between petty rulers so common in eleventh century France: such behaviour was unsuitable for would-be emperors. Instead, the often tedious Carolingian rhetoric of peace, brotherhood and the good of the Christian people corresponded to and helped produce what sometimes looks disconcertingly like everyday family squabbles on an empire-wide scale. Ninth-century political rhetoric sometimes amounts to little more than ornamented versions of you started it first – no, you started it first, my brothers are ganging up on me, and Im better than you are, but at the same time it helped place an important brake on how far such internal family feuds could be taken.