Disciplinary Connections uncovers the intertwined origins of two fields that shaped nineteenth-century thought: history and physics. Offering the first combined perspective on their development, Sjang ten Hagen reveals a time when these disciplines were seen as parallel modes of knowledge rather than as opposites within the "sciences" and "humanities." Focusing on German-speaking scholars, this book traces how historians and physicists mutually influenced one another-sharing research practices, teaching methods, and emerging ideals of "fact" and "exactitude." By examining their reciprocal evolution, this book shows how both fields helped define what counted as reliable knowledge in modern academia. It provides a new model for understanding how intellectual disciplines take shape, and it challenges the notion of rigid boundaries between the sciences and the humanities. With this innovative study Sjang ten Hagen reframes the history of knowledge as a shared enterprise across the supposed divide between scientific and humanistic inquiry.