After their failure to secure the control of government in Georgia following the Russian Revolution of 1917, most of the Bolshevik Georgian leaders relocated to Soviet Russia, from where they guided underground activities aimed at undermining the Menshevik-dominated government in Tiflis. A series of attempts to lead a peasant revolution against the Mensheviks were rendered abortive from 1918 to 1919, but preparations for a larger-scale revolt had been set in motion. The overthrow of the Democratic Republic of Azerbaijan by the Red Army in April 1920 created a precedent for the Bolsheviks in Georgia. Georgia had been in a defense alliance with Azerbaijan since 1919, but the Menshevik government hesitated to get involved in the conflict. In his April 30 speech, Georgian Premier Noe Zhordania stated that his country had been prepared to come to aid to Azerbaijan provided that the latter's own people fought for their independence. But as the Reds met minimal resistance in Baku, the Georgian government chose not to, a decision that was heavily criticized by the opposition. In conclusion, Zhordania declared that Georgia, if attacked, would defend its independence.

Answer this question based on the article: How many years after the Russian Revolution did the Red Army overthrow the Democratic Republic of Azerbaijan?
3