alternatehistory.com

The Third Balkan War, as we all know, started because some stupid Serbian nationalistic hotheads assassinated the Archduke Franz Ferdinand in June of 1914. About a month later, the Austro-Hungarian Empire declared war on Serbia. Despite stronger than expected resistance, the Serbs were defeated by the spring of 1915.

What is not widely known is that one of the reasons the Serbs felt they might be able to get away with assassinating Archduke Ferdinand is that they felt the Russian Empire would protect them from Austro-Hungarian reprisals. IOTL, the Russians were deterred when it became clear that supporting the Serbians would mean war with Germany.

WI the Russians had been a little more bold (or a little more reckless, perhaps) and announced that they would come to the support of Serbia if Austria-Hungary attacked them? Would Austria-Hungary have still gone to war? Would the Germans have supported them, or backed down? Could this event have possibly lead to a general European war?
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