The history of the outbreak of war 100 years ago and of the collapse of the fragile balance of power in Europe in the summer of 1914 is a disturbing tale of the failure of the governing elites and the military, but also of diplomacy. This is not only the case for the fateful days of July 1914. Relations between the continental great powersand their interlinked or even interrelated ruling dynasties had been built on sand long before the chain of political misjudgments and military mobilisation was set in motion.