Garni is rich in history. The area was fist occupied in the 3rd millennium BC along easily defensible terrain at one of the bends of the Azat River. In the 8th century BC the area was conquered by the Urartian King Argishti I. The fortification at Garni was erected probably sometime in the 3rd century BC as a summer residence for the Armenian Orontid and Artaxiad royal dynasties. Later around the 1st century BC the fortress of Garni became the last refuge of King Mithridates of Armenia, where he and his family were assassinated by his son in law and nephew Rhadamistus. The fortress was eventually sacked in 1386 by Timur Lenk. In 1679 an earthquake devestated the area destroying the temple.

Much of the population today descends from people settled in the population exchange of 1829–1830, following the Treaty of Turkmenchay between Russia and Persia.