The Azerbaijan Democratic Republic and the First Republic of Armenia declare their independence.

The First Republic of Armenia, officially known at the time of its existence as the Republic of Armenia (classical Armenian: ), was the first modern Armenian state since the loss of Armenian statehood in the Middle Ages.The republic was established in the Armenian-populated territories of the disintegrated Russian Empire, known as Eastern Armenia or Russian Armenia. The leaders of the government came mostly from the Armenian Revolutionary Federation (ARF or Dashnaktsutyun). The First Republic of Armenia bordered the Democratic Republic of Georgia to the north, the Ottoman Empire to the west, Persia to the south, and the Azerbaijan Democratic Republic to the east. It had a total land area of roughly 70,000 km2, and a population of 1.3 million.

The Armenian National Council declared the independence of Armenia on 28 May 1918. From its very onset, Armenia was plagued with a variety of domestic and foreign issues. A humanitarian crisis emerged from the aftermath of the Armenian genocide as hundreds of thousands of Armenian refugees from the Ottoman Empire were forced to settle in the fledgling republic. Lasting two and a half years in existence, the Republic of Armenia became involved in several armed conflicts with its neighbors, caused by overlapping territorial claims. By late 1920, the nation was partitioned between the Turkish Nationalist forces and Russian Red Army. The First Republic, along with the Republic of Mountainous Armenia which repelled the Soviet invasion until July 1921, ceased to exist as an independent state, superseded by the Armenian Soviet Socialist Republic that became part of the Soviet Union in 1922. After the fall of the Soviet Union, the republic regained its independence as the current Republic of Armenia in 1991.

The Azerbaijan Democratic Republic (ADR; Azerbaijani: Azərbaycan Demokratik Cümhuriyyəti), was the first secular democratic republic in the Turkic and Muslim worlds. The ADR was founded by the Azerbaijani National Council in Tiflis on 28 May 1918 after the collapse of the Transcaucasian Democratic Federative Republic, and ceased to exist on April 28 1920. Its established borders were with Russia to the north, the Democratic Republic of Georgia to the north-west, the Republic of Armenia to the west, and Iran to the south. It had a population of around 3 million. Ganja was the temporary capital of the Republic as Baku was under Bolshevik control. The name of "Azerbaijan" which the leading Musavat party adopted, for political reasons, was, prior to the establishment of the Azerbaijan Democratic Republic in 1918, exclusively used to identify the adjacent region of contemporary northwestern Iran.Under the ADR, a government system was developed in which a Parliament elected on the basis of universal, free, and proportionate representation was the supreme organ of state authority; the Council of Ministers was held responsible before it. Fatali Khan Khoyski became its first prime minister. Besides the Musavat majority, Ahrar, Ittihad, Muslim Social Democrats as well as representatives of Armenian (21 out of 120 seats), Russian, Polish, and Jewish minorities gained seats in the parliament. Many members supported Pan-Islamist and Pan-Turkist ideas.Among the important accomplishments of the Parliament 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. Another important accomplishment of the ADR was the establishment of Baku State University, which was the first modern-type university founded in Azerbaijan.