Armenian–Azerbaijani War
Historically both Armenia and Azerbaijan lay claim to some of the same territories, an issue complicated by the intermingling of ethnic populations so some areas have no clearly demarcated Azeri and Armenian border; these potential sources of conflict remained quiescent whilst both nations were subsumed by greater powers. However, the collapse of the Ottoman and Russian Empires in the wake of the First World War led to the 
. With the demise of the short-lived Armenian-Azerbaijan-Georgia Transcaucasian Democratic Federative Republic, fighting broke out which only ended when the two nations were annexed by the expanding Soviet Union.
Release and pardon of killer jeopardises Armenia-Azerbaijan ceasefire