Answer :
Austria accused Serbia in The Causes of World War One, prompting Serbia to seek assistance from Russia. In support of Austria and France due to her partnership with Russia, Germany declared war on Russia. In support of Belgium and France, as well as Turkey due to her connection with Germany, Britain declared war on Germany.
The Russian Empire slowly enrolled in World War I over the course of the three days preceding July 28, 1914. This began when Serbia, who was at the time an ally of Russia, was proclaimed at war by Austria-Hungary. The Russian Empire set Austria-Hungary a deadline to refrain from attacking Serbia through St. Petersburg. After the invasion of Serbia, Russia began to station its reserve force close to the border with Austria-Hungary. Therefore, on July 31, Russian demobilization was required by the German Empire in Berlin. That day, Germany declared war on Russia due to the lack of a response. On August 3, Germany disregarded Russia and launched its onslaught against France in accordance with its war plan. Belgium was the destination that Germany's main forces traveled to.
Learn more about Russia from
brainly.com/question/1105404
#SPJ