This book - based on an analysis of both written and archaeological sources - presents an overall view of the royal castles of Denmark. Profusely illustrated, it focuses on the various functions of the royal castles and how they were used in peacetime and war. During the turbulent 14th century, control of these castles was a prerequisite for maintaining the monarch's authority and for defending the kingdom against internal rebels, as well as foreign enemies. New castles were erected and older castles were rebuilt all over Denmark, especially during the reign of King Erik Menved (1286-1319) and King Valdemar Atterdag (1340-1375). The development of castle-building is also examined in the context of the building traditions elsewhere in Europe.