Chapter 4 picks up the themes floated in Chapter 1 and applies them to the urban context. It begins with the interest in childhood among European nation-states from the middle of the eighteenth century onwards, provoked by awareness of their high infant mortality rates. The start of national systems of education in certain countries was a symptom of this concern, influencing the boundaries of childhood with its age-graded system of classes. The Enlightenment thinkers of the eighteenth century were influential on thoughts on the nature of the child, bringing a more secular approach to childhood than in the past. Two key works stand out here: Some Thoughts Concerning Education, by John Locke, and Emile, by Jean-Jacques Rousseau. The Romantic movement that followed went further in seeing a spiritual wisdom to the child, lacking in adults. Finally, the chapter documents the growing perception that childhood was an important stage in life, with a number of famous authors writing books entirely devoted to their own early years.