A History of Russian-Iranian Relations The thematic question of this paper is the nature of Iran’s relations with Russia focusing on the nineteenth and twentieth centuries. My revisionist thesis departs from mainstream historiography by suggesting that Russia has been at least as important as Great Britain and the U.S. in shaping modern Iranian history. Methodologically, I replace Eurocentric assumptions by a global historiographic perspective, assigning Russia a central constructive impact on modern Iranian history. The paper will draw upon Persian primary and archival sources, recent scholarly compilations edited by Cronin (2013) and Matthee and Andreeva (2018), and book chapters and a monograph by the presenter (2018). Following imperial Russia’s expansion to Iranian borders, military, economic, political and cultural interactions with Iran began in the eighteenth century, intensified during the nineteenth century and peaked in the twentieth-century Soviet era. Cold War and Great Game historiography assumes a detrimental impact on Iran, as well as negative perceptions among Iranians of both imperial Russia and the Soviet Union. Challenging such assumptions, I will show that nineteenth-century Iranian political perceptions tended to be more anti-British than anti-Russian. During the 1905-1911 Constitutional Revolution, Russo-Caucasian social democracy made a major ideological impact on Iran, later intensified by the Bolshevik Revolution. Countering mainstream historiography, I will show that 1920s Bolshevik support for a Soviet republic in Iran had domestic backing and was defeated primarily due to British intervention. Under Reza Shah Pahlavi (1926-1941), the Soviet Union remained Iran’s largest trade partner, exerting significant cultural and political influence, despite the Pahlavi regime’s anti-communism. The greatest impact of the USSR, however, came with its WWII occupation of northern Iran, leading to the formation of the communist Tudeh Party, whose social reform program made it incomparably popular, while establishing Marxist intellectual hegemony in mid-century Iran. Disillusionments notwithstanding, the Soviet model of building modernity remained attractive to two generations of educated Iranians, while the Communist Party’s agenda served as the basic template for 1960s-1970s Iran’s modernization and social reform. Soviet-style Marxism was a crucial political and ideological factor shaping Iran’s 1978-1979 Revolution, in whose aftermath the Islamic Republic fought a small civil war to eradicate the revolution’s Marxist and Islamic leftist factions. Fraught with tension, the Islamic Republic’s relations with the USSR were nevertheless better than with the U.S., while in recent post-Soviet decades, Iran has formed a semi-strategic military-political alliance with the Russian Federation.