The Independence Day of Armenia (Armenian: Հայաստանի Անկախության օրը) is the main state holiday in Armenia. This date is celebrated on September 21. This is the second independence of Armenia. The first occurred on May 28, 1918 and led to the formation of the First Republic of Armenia.
This republic was then taken over by the USSR in 1920, also commonly referred to as Soviet Armenia, one of the constituent republics of the Soviet Union in December 1922 located in the South Caucasus region of Eurasia.
It was established in December 1920, when the Soviets took over control of the short-lived First Republic of Armenia and lasted until 1991. It is sometimes called the Second Republic of Armenia, following the First Republic of Armenia’s demise.
On August 23, 1990, Supreme Council adopted the Declaration of State Sovereignty of Armenia proclaiming the Armenian SSR abolished and the establishment of the Republic of Armenia. On September 21, 1991, the people of Armenia voted in a referendum to proclaim independence from the Soviet Union. Levon Ter-Petrosyan was elected the first president of Armenia in November 1991.
On December 21, 1991, Armenia joined the Commonwealth of Independent States (CIS). Armenia gained independence formally on December 26 in connection with the dissolution of the USSR.