>>514064492
Some wider context:
For the entire century prior to WW1, Austria and Russia had been at loggerheads over "The Ottoman Question"
The Ottoman Empire was crumbling and the Great Powers of Europe had different ideas of what to do about it. Austria favoured propping the Ottomans up to avoid a catastrophic collapse and power vacuum in the region, believing the Ottomans existing would help maintain stability in the region. Britain and France both backed Austria in this.
Russia wanted to deliver the coup de grace, end the Ottoman Empire and claim Thrace and Anatolia for itself. They coveted Istanbul and the Dardanelles as warm water port for its Black Sea Fleet, aspiring to gain unfettered military access to the Mediterranean and build up a navy that could challenge the british for control there.
Russia had attempted to force the issue before, which had led to the Crimean War and their utter humiliation. Thus they shifted tactics instead, aiming to foment unrest in the Balkans, install pro-russian puppet governments and use them as proxies to attack and secure Istanbul. Since the Balkan states had legitimate grievances with the Ottomans, it would give Russia plausible deniability. Then, once Istanbul had fallen, they would simply annex their puppets and the conquest would be fait accompli. They directly promoted both Balkan Wars to this end, which backfired spectacularly.
Since the Austro-Hungarian Empire was the main obstacle to Russia's proxies having a free hand in the Balkans, Russia directed its proxies against them, which led to the formation of the Black Hand (among countless other Russia-aligned Serbian nationalist groups) and the eventual assassination that sparked the World War.
This isn't a dig against Russians. Nobody blames the people living in serdom for the actions of their despot, but it's an indisputable fact that the actions of that despot and his regime directly led to the outbreak of the Great War.