Background to the holy wars and the First Crusade's conquest of Jerusalem, a holy city for Jews, Christians and Muslims.
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President of Azerbaijan, Ilham Aliyev, addresses the media prior to a North Atlantic Council (NAC) meeting at the NATO headquarters in Brussels, Belgium, 15 January 2014. (EPA/THIERRY MONASSE)
A series of combative tweets posted by the President of Azerbaijan are generating controversy during renewed fighting between the Armenian and Azeri armies. An uneasy twenty year truce over the disputed Nagorno Karabakh region ended when clashes led to the deaths of at least four Azeri troops and one ethnic Armenian soldier. The territory has a large ethnic Armenian population and has been controlled primarily by Armenian troops and local fighters.
Since hostilities broke out, President Aliyev took to Twitter to threaten war, while calling Armenians "barbarians and vandals".