Imperium Christianum

Abstract This chapter explains why Christian kingship became politically meaningful in the Carolingian Empire in the 830s. It argues that a concept of bishops as co-rulers (with kings) of the Christian people emerged distinctively in the Carolingian Empire, not elsewhere in the Latin West at this time. Christianity became central to discourses about political responsibility and political relationships during the reign of Louis the Pious; from the later part of Charlemagne’s reign lay and clerical elites saw themselves as sharing, under their Carolingian monarchs, in a quest to achieve the ideal Christian society. Political crisis and the breakdown of elite relationships made appeals to the idea that a sinner could not rule useful late in Louis’s reign. This marked the loss of a late antique secularity in one regard, but it was only ever partial; alternatives to Christian kingship remained available for Carolingian elites to use when it suited them.