The Nagorny Karabakh conflict is the longest-running unresolved dispute in the former Soviet Union, dating back to the middle of the Gorbachev era in 1988. It is also potentially the most dangerous, as Armenia and Azerbaijan are in a perpetual state of military readiness to go to war again over the disputed territory they fought over in 1991-94. At the end of that conflict, the Armenian side prevailed at great cost. Around 20,000 people died and one million people were displaced on both sides, the majority of them Azerbaijanis. A brief upsurge of fighting in 2016 cost around 200 lives.