This chapter shows how elites in the time of Louis the Pious discussed landed property belonging to churches, and how old Roman law was used in the process to secure that property's status. In this debate, the recourse to sixth-century Roman law enabled certain actors to assign the ruler a distinctive position standing over the community of the ecclesia. The idea that ecclesiastical property should be treated as inalienable would have an enormous impact on both legal theory and practice. For it shaped the types of transaction that could be used when dealing with church property in a characteristic manner, so that donation, precaria oblata, infeudation and exchange dominate our ecclesiastical charter evidence from the early Middle Ages onwards. As is well known, it was from the twelfth century onwards that the idea of church property as inalienable would form the starting point for a new conception of sovereignty.