World War I: The Causes
The Balkan Wars
The Balkan Wars in 1912–1913 increased international tension between Russia and Austria. It also led to a strengthening of Serbia and a weakening of Turkey and Bulgaria, who might otherwise have kept Serbia in check, thus disrupting the balance of power in Europe in favor of Russia. The conflicts demonstrated that a localized war in the Balkans could alter the balance of power without provoking general war and reinforced the attitude in the Austrian government. This attitude had been developing since the Bosnian annexation crisis that ultimatums were the only effective means of influencing Serbia and that Russia would not back its refusal with force. They also dealt catastrophic damage to the Habsburg economy.