Comparative law, both as a method of legal science and as an academic discipline, is largely a product of modern Western thought. However, this does not imply that legal comparison was absent in earlier civilizations. From an early period, people recognized that legal norms varied across societies, and these differences were sometimes considered when developing new legal rules and institutions. The underlying rationale appears to have been that the laws of politically dominant or culturally advanced states and communities were deliberately imitated or adopted by others, a process that likely occurred in various regions throughout history. This chapter explores the role of legal comparatism in ancient, medieval, and early modern European legal thought and practice, tracing key ideas that contributed to the emergence of comparative law. Particular attention is given to the development of the comparative approach to law during the Renaissance and Enlightenment, an era defined by the rise of scientific rationalism, the modern nation-state, and national legal systems.