This book examines the significance of alliances in the international system, focusing on the dynamics between great and regional powers, and on the alliances Nazi Germany made during World War II, and their implications for Germany. It examines a variety of case studies and looks at how each of the respective states contributed to or weakened Nazi Germany’s warfighting capabilities. The cases cover the principal Axis members Italy and Japan, secondary Axis allies Hungary and Romania, as well as neutral states that had economic and military significance for Germany, namely Bulgaria, Iran, Spain, Sweden, Switzerland, Turkey, and Vichy France. Additional case studies include topics such as the German attempts to cultivate Arab nationalism, focusing on German involvement in the coup in Iraq against the pro-British government, and the wartime state of Croatia, whose creation was made possible by Germany, with the rivalry between Germany and Italy for control being a major focus. The book also includes a case study exploring the unique position of Finland among German allies as a democracy and how the country was essentially fighting a very different war from Nazi Germany. This will be of interest to students and academics with an interest in power dynamics in World War II, economic, political, strategic, and alliance theory, and scholarly debate on Nazism and Europe.