From the 15th century, Armenia had been part of the Ottoman Empire. By the 19th century, most of modern-day Armenia had come under the control of the Russian Empire. 

With the Russian revolution ending the empire and the collapse of the Democratic Republic of Transcaucasia, the Armenian National Council Declared its sovereignty on May 28th 1918 and the First Armenian Republic was proclaimed, restoring Armenian statehood after six centuries of foreign control. 

The republic proved to be short-lived. On December 2nd 1920, the Armenian government headed by Prime Minister Simon Vratsyan signed a treaty with the Bolsheviks and the Red Army entered Armenia and proclaimed it a Soviet Republic. The Armenian Soviet Socialist Republic became a founding member of the Soviet Union in 1922. 

Armenia regained its independence as the current Republic of Armenia on September 21st 1991, following the collapse of the Soviet Union. Armenia was the first non-Baltic republic to secede from the Soviet Union. This event is celebrated on Independence Day.