Although many recent studies have addressed important aspects of medieval southern Italy, this is the first work for nearly ninety years to be devoted specifically to the life and reign of King Roger II, the founder of the kingdom of Sicily. The book provides a comprehensive introductory narrative of the reign, and a clear, scholarly and up-to-date analysis of its culture and of the development of royal government. The kingdom created by the Norman Roger of Hauteville in the first half of the twelfth century was a monarchy with highly developed absolutist ideas, an elaborate bureaucracy, a reasonably well-filled treasury, and a mixed cultural heritage reflected by the presence of Arabs and Greeks at court. Based on many years of research in archives and libraries across Europe, the book offers a valuable overview of one of the most striking periods in south Italian and European history.