This book offers a sociological analysis of the history of international police cooperation in the period from the middle of the 19th century until the end of World War II. It is a detailed exploration of international cooperation strategies involving police institutions from the United States and Germany as well as other European countries. The study provides a rich empirical account of many dimensions in the history of international policing, including the role of police in the 19th-century national independence movement; the evolution from simple cooperation towards international criminal enforcement duties; international policing aspects of the outbreak of World War I and the Bolshevik Revolution; the early history of international police organizations, including Interpol; the international implications of the Nazification of the German police; and the rise on the international scene of the Federal Bureau of Investigation. To account for these historical transformations, this book develops an innovative theoretical model of bureaucratization based on the sociology of Max Weber and theories of globalization. It is argued that international police cooperation is enabled through a historical process of police agencies gradually claiming and gaining a position of relative independence from the governments of their respective states. Furthermore it shows that international police cooperation relies on expert systems of knowledge on international crime, which police institutions across nations develop and share. Paradoxically, in spite of this spirit of cooperation, national concerns of participating forces remain paramount.