Leader who declared war on russia to support austria hungary?
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Political leader who declared war on russia to support austria hungary?
Wilhelm II Wilhelm II, German Emperor, the Kaiser William II
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Military leader who declared war on russia to support austria hungary?
Chief of the German General Staff Moltke the Younger Moltke Helmuth Johannes Ludwig Graf von Moltke Helmuth von Moltke
German entry into World War I
https://en.wikipedia.org/wiki/German%20entry%20into%20World%20War%20I
Russian entry into World War I
https://en.wikipedia.org/wiki/Russian%20entry%20into%20World%20War%20I
Wilhelm II, German Emperor
https://en.wikipedia.org/wiki/Wilhelm%20II%2C%20German%20Emperor
Wilhelm II (Friedrich Wilhelm Viktor Albert; 27 January 1859 – 4 June 1941), anglicised as William II, was the last German Emperor (Kaiser) and King of Prussia, reigning from 15 June 1888 until his abdication on 9 November 1918. 
Wilhelm II, German Emperor The Sarajevo crisis
As the war started, Germany stood behind its ally Austria-Hungary in a confrontation with Serbia, but Serbia was under the protection of Russia, which was allied to France.
German entry into World War I July: crisis and war
Wilhelm was a friend of Archduke Franz Ferdinand of Austria, and he was deeply shocked by his assassination on 28 June 1914. Wilhelm offered to support Austria-Hungary in crushing the Black Hand, the secret organisation that had plotted the killing, and even sanctioned the use of force by Austria against the perceived source of the movement—Serbia (this is often called "the blank cheque"). 
Wilhelm II, German Emperor The Sarajevo crisis
 A lax wartime leader, Wilhelm left virtually all decision-making regarding strategy and organisation of the war effort to the German Army's Great General Staff.
Wilhelm II, German Emperor The Sarajevo crisis
German Chief of Staff Moltke sent an emotional telegram to the Austrian Chief of Staff Conrad on July 30: "Austria-Hungary must be preserved, mobilise at once against Russia. Germany will mobilise." Vienna officials decided that Moltke was really in charge—which was true—and refused mediation and mobilized against Russia.[38]
German entry into World War I July: crisis and war
Wilhelm II  anglicised as William II, was the last German Emperor (Kaiser) and King of Prussia, reigning from June 15, 1888 until his abdication on November 9, 1918. Wilhelm was a friend of Archduke Franz Ferdinand of Austria, and he was deeply shocked by his assassination on June 28, 1914. Wilhelm offered to support Austria-Hungary in crushing the Black Hand, the secret organisation that had plotted the killing, and even sanctioned the use of force by Austria against the perceived source of the movement,Serbia, but Serbia was under the protection of Russia, which was allied to France. Wilhelm left virtually all decision-making regarding strategy and organisation of the war effort to the German Army's Great General Staff. German Chief of Staff Moltke sent an emotional telegram to the Austrian Chief of Staff Conrad on July 30: "Austria-Hungary must be preserved, mobilise at once against Russia. Germany will mobilise." Vienna officials decided that Moltke was really in chargeand refused mediation and mobilized against Russia.