Before Gavrilo Princip fired his pistol, what set of conditions made war in Europe almost unavoidable?

Before gavrilo princip fired his pistol, there are set of conditions that made war in europe almost unavoidable that he said. a series of political changes happened on that time in europe in which made war almost unavoidable. the nineteen fourteen europe was ripe for war, most of europe plunged into war within five weeks.