The Russian Empire was overthrown by the short-lived February Revolution in 1917. The national movement of people who were trampled by the tyranny existed in the country started. On 28 May 1918 the Azerbaijan Democratic Republic, the first secular democratic state in the Muslim East was proclaimed. The Azerbaijan Democratic Republic, founded by Mammad Amin Rasulzadeh, was the first parliamentary republic and the first democratic, legal and secular state in the Turkish and Islamic world. Among the important accomplishments of the ADR was the extension of suffrage to women, making Azerbaijan one of the first countries in the world, and the very first majority-Muslim nation, to grant women equal political rights with men. The first state, which officially recognized the Azerbaijan Democratic Republic was the Ottoman Empire. That historic event took place on 4 June 1918. On 9 November 1918 on the basis of the proposal by Mammad Amin Rasulzadeh the three-color flag of the Azerbaijan Democratic Republic was adopted. Until then the flag of the Azerbaijan Democratic Republic was red. The Azerbaijan Democratic Republic was able to operate in a tense and complicated socio-political situation for only 23 months. The Soviet Union invaded Azerbaijan on 28 April 1920. Though the idea of independence was not defeated, and in 1991, after the collapse of the Soviet Empire, Azerbaijan again declared its independence.
One year after the founding of the ADR, a military parade on the site of the Azerbaijan Carpet Museum took place. In honor of this day the station of the Baku underground is named. Initially, it was called "April 28", since on 28 April 1920, Soviet power was established in Azerbaijan, and the ADR ceased to exist. However, after the Republic gained independence for the second time, the name, reminiscent of the Soviet past, was replaced by "May 28". It was enough to rename only letters, the numbers remained the same. In honor of this day a street in Baku was named, the Istiglaliyyat Street. On the Istiglaliyyat Street, a stele with the text of the Declaration of Independence was installed. On the wall of the hall of the former palace of the governor in the Caucasus in Tbilisi, where the republic was proclaimed, a memorial plaque with an inscription in Azerbaijani, Georgian and English languages was installed. In 2008, a postage stamp was issued in connection with the 90th anniversary of the Republic.