Twice in the decade before the Thirty Years' War the Jülich-Kleve succession placed Europe on the verge of war. Located along the Rhine River on the borders of the divided Netherlands, the Jülich-Kleve duchies possessed great political, economic, and religious importance which attracted the interest of all the major European powers of the day. Yet despite the strategic location of the duchies and the international involvement in the succession disputes, diplomacy triumphed, and war was averted. This book examines the Jülich-Kleve succession crises from a wide, international perspective in order to explain how the thorny succession disputes could be successfully resolved through diplomacy. In so doing, this book reevaluates the significance not only of the Jülich-Kleve succession but also of international relations on the eve of the Thirty Years' War.