This series looks at groups of people, often ordinary people, who did historically significant things, and how we know about their lives and events. Each book shows how we know about the people and their experiences from primary and other sources. It includes information on some historical detective work that has taken place, using documentary, archaeological, and oral evidence, that has enabled historians to piece together fascinating stories, from the escape of slaves on the Underground Railroad to the epic journeys of exploration by lunar astronauts.