The Kievan Rus developed close ties with the Byzantines, leading early Russia to adopt Byzantine Christianity, particularly after the Christianization of Kievan Rus in 988 under Prince Vladimir the Great. This event marked the beginning of a significant cultural and religious transformation in the region.
The first Russian empire, known as the Tsardom of Russia (and later the Russian Empire), revered the Roman and Byzantine empires. It adopted the title of "Tsar" (derived from "Caesar") for its emperors in honor of former rulers in Rome, which reflected the desire to align itself with the legacy and authority of these great empires. This connection was further emphasized by the belief that Moscow represented the "Third Rome," a notion that sought to position it as the successor to the political and religious authority of both Rome and Constantinople.