two, the Russo-Persian War of 1826–1828. The resulting Treaty of Turkmenchay, forced Qajar Iran to cede sovereignty over the Erivan Khanate, the Nakhchivan Khanate and the remainder of the Talysh Khanate, comprising the last parts of the soil of the contemporary Azerbaijani Republic that were still in Iranian hands. After the incorporation of all Caucasian territories from Iran into Russia, the new border between the two was set at the Aras River, which, upon the Soviet Union's disintegration, subsequently became part of the border between Iran and the Azerbaijan Republic. Qajar Iran was forced to cede its Caucasian territories to Russia in the 19th century, which thus included the territory of the modern-day Azerbaijan Republic, while as a result of that cession, the Azerbaijani ethnic group is nowadays parted between two nations: Iran and Azerbaijan. Despite the Russian conquest, throughout the entire 19th century, preoccupation with Iranian culture, literature, and language remained widespread amongst Shia and Sunni intellectuals in the Russian-held cities of Baku, Ganja and Tiflis (Tbilisi, now Georgia). Within the same century, in post-Iranian Russian-held East Caucasia, an Azerbaijani national identity emerged at the end of the 19th century. After the collapse of the Russian Empire during World War I, the short-lived Transcaucasian Democratic Federative Republic was declared, constituting the present-day republics of Azerbaijan, Georgia, and Armenia. It was followed by the March Days massacres that took place between 30 March and 2 April 1918 in the city of Baku and adjacent areas of the Baku Governorate of the Russian Empire. When the republic dissolved in May 1918, the leading Musavat party declared independence as the Azerbaijan Democratic Republic (ADR), adopting the name of "Azerbaijan" for the new republic; a name that prior to the proclamation of the ADR was solely used to refer to the adjacent northwestern region of contemporary Iran. The ADR was the first modern parliamentary republic in the Muslim world. Among the important accomplishments of the Parliament was the extension of suffrage to women, making Azerbaijan the first Muslim nation to grant women equal political rights with men. Another important accomplishment of ADR was the establishment of Baku State University, which was the first modern-type university founded in the Muslim East. By March 1920, it was obvious that Soviet Russia would attack Baku. Vladimir Lenin said that the invasion was justified as Soviet Russia could not survive without Baku's oil. Independent Azerbaijan lasted only