This detailed study of Normandy’s frontiers in the twelfth century explores how the dukes of Normandy, who were also usually kings of England, controlled the borders of their realm, and how the local aristocracy responded to their rule. The book discusses ties of land and kinship among the frontier lords, and how the political borders affected government, law, the Church, and the fortunes of the local nobility. It culminates in a major discussion of the annexation of Normandy by the kings of France in 1204.