The Christian Empire early in the fifth century began to face a rapid series of grave political crises. Although Roman governments had weathered innum erable earlier emergencies during a turbulent history that stretched back more than a millennium, the fifth-century invasions inflicted irreversible wounds. The Empire in the West failed to survive.1 The crises of the fifth and sixth centuries centred upon the successful invasion of the Western Empire by Germanic peoples, who subsequently settled in and secured political control of the whole region that we now describe as Western Europe. The new ethnic and political order in the West inevitably altered the relationship between ecclesiastical institutions and civil governments, as Germanic kingdoms began to replace the political and legal structures of the old Western Empire. Those changes, in turn, shaped the subsequent development of the church’s own institutional structures and its legal system.