What country was the first to declare war, in what became WWI?
Archduke Franz Ferdinand, of Austria-Hungary was murdered by a Serbian born anarchist, in Sarajevo Bosnia June 1914. The Archduke was the heir to the Austria-Hungary empire, and Serbia, was blamed for the murder.
Austria-Hungary first made a list of demands that it presented to Serbia. When the demands were not met in full, Austria-Hungary declared war on Serbia.
Russia which had an alliance with Serbia, mobilized it's troops and prepared to defend Serbia. Germany mobilized to defend it's ally Austria-Hungary, from Russian intervention. This was how the great war began, it was a regional issue that spiraled out of control.
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