This is the first comparative and thematic study of royal childhood and child kingship between the eleventh and thirteenth centuries. It demonstrates children’s centrality to medieval rulership and helps to refine resolutely adult-focused perspectives on kingship. The book centres around eight case studies: Henry IV of Germany, Philip I of France, Malcolm IV, king of Scots, Philip II of France, Frederick II of Sicily and Germany, Henry III of England, Louis IX of France and Alexander III, king of Scots. Interweaving these examples with a wide variety of historical, documentary, legal, artistic and literary evidence, the book balances representation and reality while showing the significance of change over time. Part I illustrates the problematic nature of working from the assumption that kingship was equivalent to adult power. Part II emphasises how the upbringing and education royal children received equipped them for kingship and prepared the wider political community to accept and support child rulers. Part III shifts to focus on the years after a child’s succession and considers issues of terminology and legality, political innovation, conflict and the life cycle.