Respuesta :
Answer:
Nationalism caused Serbia to want to absorb all Slavs on the Balkan Peninsula. Russia supported this but Austria-Hungary felt that it would stir up rebellion among it's Slavic population.
Russia declare war on Austria-Hungary because it wanted to control the Balkans, and liberating other slavic nations.
Russian Declaration of War
The decision of Austria-Hungary to attack on Serbia, was not gone well with Russia, because of shared history and culture as well as the political objective of Russia to control the Balkan territory.
Apart from this Serbian Nationalism was more tilted towards Russia rather than Austria or Ottoman empire. Therefore, because of Political and social reasons, Russia declared war on Austria-Hungary.
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