Answer: One of the major causes of tensions in Europe that led to World War I was the complex web of alliances between European powers. This included the informal "Triple Entente" (Great Britain, France, and Russia) and the secret "Triple Alliance" (Germany, the Austro-Hungarian Empire, and Italy)⁴. Other factors included political, territorial, and economic competition; militarism; imperialism; the growth of nationalism; and the power vacuum created by the decline of the Ottoman Empire¹. The assassination of Archduke Franz Ferdinand of Austria by the Bosnian Serb nationalist Gavrilo Princip, who had been supported by a nationalist organization in Serbia, also played a significant role¹². This assassination set off a rapidly escalating chain of events, leading to the outbreak of the war².