Final answer:
Russia supported Serbia due to ideological alignment, historical conflicts with Austria-Hungary and Ottoman Empire, and a desire to protect Slavic nations.
Explanation:
Russia ended up backing Serbia and declaring war on Austria-Hungary for multiple reasons:
- Russia's leaders were ideologically aligned with the Serbian efforts to expel Slavic peoples from the Balkans.
- Russia had historically clashed with both the Austro-Hungarian and Ottoman empires.
- Overall, Russia hoped to cultivate access to the Mediterranean Sea and protect its fellow Slavic nation, Serbia.
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