Encouraged by Russia, the a Balkan league is formed by Bulgaria, Greece, Montenegro and Serbia, with the aim of pushing Turkey out of Europe. Using the Albanian revolt as pretext, the league goes to war in 1912. Turkey is already weakened by the recent war with Italy over Tripolitania, and is driven out of the Balkans in seven weeks.
Austria-Hungary is horrified, facing a strengthened Serbia, and the military calls for war. It is, however, deterred by the idea of Russia supporting Serbia, as well as lack of German support. British Foreign Secretary, Sir Edward Grey, is anxious to stop the war spreading, and the war is settled with the Treaty of London. The former Turkish lands are divided amongst the victors, but Austria-Hungary succeeds in containing Serbia through the creation of Albania, which separates Serbia from the Adriatic Sea. The War increases Austro-Serbian tensions, especially after it is discovered that Serbia has not withdrawn its forces from Albanian territory, but rather occupied more. Austro-Hungary sends an ultimatum to the Serbians, and the Serbians withdraw. This teaches Austro-Hungary that threatening to use force will win.