The book investigates the quest for international security in mid-19th century Germany from a new and inspiring perspective. Under the influence of international events, Germans believed that they lived in dangerous times when relations between countries and nations were increasingly defined by the law of the strongest instead of written law. Regardless of their origin, political views, gender and social status they participated in debates about the future of Germany, Europe and the world and tried to determine how to better ensure external security, develop justice and achieve a more stable peace. This fundamental but hitherto historiographically neglected process became manifest in numerous phenomena analysed independently in the past such as the participation in the organised peace movement, the rise of German nationalism, the call for land and naval armaments, the aspiration to colonial expansion, the birth of Realpolitik and the concept of Mitteleuropa, and the deterioration in relations and wars with other nations. Although it did not last long, the process became significant for the negative consequences it had for the rest of the century. For today's reader it presents a warning about how society is impacted and the stability of an international order is undermined by a declining confidence in international justice and the durability of peace.