Christianization of Kievan Rus' in the context of "Russian Orthodoxy"

The recorded history of the Crimean Peninsula, historically known as Tauris, Taurica (Greek: Ταυρική or Ταυρικά), and the Tauric Chersonese (Greek: Χερσόνησος Ταυρική, "Tauric Peninsula"), begins around the 5th century BCE when several Greek colonies were established along its coast, the most important of which was Chersonesos near modern-day Sevastopol, with Scythians and Tauri in the hinterland to the north. The southern coast gradually consolidated into the Bosporan Kingdom which was annexed by Pontus and then became a client kingdom of Rome (63 BC – 341 AD). The south coast remained Greek in culture for almost two thousand years including under Roman successor states, the Byzantine Empire (341–1204), the Empire of Trebizond (1204–1461), and the independent Principality of Theodoro (ended 1475). In the 13th century, some Crimean port cities were controlled by the Venetians and by the Genovese, but the interior was much less stable, enduring a long series of conquests and invasions. In the medieval period, it was partially conquered by Kievan Rus' whose prince Vladimir the Great was baptised at Chersonesus Cathedral, which marked the beginning of the Christianization of Kievan Rus'. During the Mongol invasion of Europe, the north and centre of Crimea fell to the Mongol Golden Horde, and in the 1440s the Crimean Khanate formed out of the collapse of the horde but quite rapidly itself became subject to the Ottoman Empire, which also conquered the coastal areas which had kept independent of the Khanate. A major source of prosperity in these times was frequent raids into Russia for slaves for the Crimean slave trade.

In 1774, the Ottoman Empire was defeated by Catherine the Great. After two centuries of conflict, the Russian fleet had destroyed the Ottoman navy and the Russian army had inflicted heavy defeats on the Ottoman land forces. The ensuing Treaty of Küçük Kaynarca forced the Sublime Porte to recognize the Tatars of the Crimea as politically independent. Catherine the Great's incorporation of the Crimea in 1783 from the defeated Ottoman Empire into the Russian Empire increased Russia's power in the Black Sea area. The Crimea was the first Muslim territory to slip from the sultan's suzerainty. The Ottoman Empire's frontiers would gradually shrink, and Russia would proceed to push her frontier westwards to the Dniester. From 1853 to 1856, the strategic position of the peninsula in controlling the Black Sea meant that it was the site of the principal engagements of the Crimean War, where Russia lost to a French-led alliance.

The Slavs were Christianized in waves from the 7th to 12th century, though the process of replacing old Slavic religious practices began as early as the 6th century. Generally speaking, the monarchs of the South Slavs adopted Christianity in the 9th century, the East Slavs in the 10th, and the West Slavs between the 9th and 12th century. Saints Cyril and Methodius (fl. 860–885) are attributed as "Apostles to the Slavs", having introduced the Byzantine-Slavic rite (Old Slavonic liturgy) and Glagolitic alphabet, the oldest known Slavic alphabet and basis for the Early Cyrillic alphabet.

The simultaneous missionary efforts to convert the Slavs by what would later become known as the Catholic Church of Rome and the Eastern Orthodox Church of Constantinople led to a 'second point of contention between Rome and Constantinople', especially in Bulgaria (9th–10th century). This was one of many events that preceded the East–West Schism of 1054 and led to the eventual split between the Greek East and Latin West. The Slavs thus became divided between Eastern Orthodoxy and Roman Catholicism. Closely connected to the competing missionary efforts of the Roman Church and the Byzantine Church was the spread of the Latin and Cyrillic scripts in Eastern Europe. The majority of Orthodox Slavs adopted Cyrillic, while most Catholic Slavs adopted the Latin, but there were many exceptions to this general rule. In areas where both Churches were proselytising to pagan Europeans, such as the Grand Duchy of Lithuania, the Croatian Duchy and the Principality of Serbia, mixtures of languages, scripts and alphabets emerged, and the lines between Latin Catholic (Latinitas) and Cyrillic Orthodox literacy (Slavia Orthodoxa) were blurred.

Kievan Rus', also known as Kyivan Rus', was the first East Slavic state and later an amalgam of principalities in Eastern Europe from the late 9th to the mid-13th century. Encompassing a variety of polities and peoples, including East Slavic, Norse, and Finnic, it was ruled by the Rurik dynasty, founded by the Varangian prince Rurik. The name was coined by Russian historians in the 19th century to describe the period when Kiev was preeminent. At its greatest extent in the mid-11th century, Kievan Rus' stretched from the White Sea in the north to the Black Sea in the south and from the headwaters of the Vistula in the west to the Taman Peninsula in the east, uniting the East Slavic tribes.

According to the Primary Chronicle, the first ruler to unite East Slavic lands into what would become Kievan Rus' was Varangian prince Oleg the Wise (r. 879–912). He extended his control from Novgorod south along the Dnieper river valley to protect trade from Khazar incursions from the east, and took control of the city of Kiev, laying the foundation of the state and becoming prince of Kiev. Sviatoslav I (r. 943–972) achieved the first major territorial expansion of the state, fighting a war of conquest against the Khazars. Vladimir the Great (r. 980–1015) spread Christianity with his own baptism and, by decree, extended it to all inhabitants of Kiev and beyond. Kievan Rus' reached its greatest extent under Yaroslav the Wise (r. 1019–1054); his sons assembled and issued its first written legal code, the Russkaya Pravda, shortly after his death.

The Russian Orthodox Church (ROC; Russian: Русская православная церковь, РПЦ, romanized: Russkaya pravoslavnaya tserkov, RPTs;), also officially known as the Moscow Patriarchate (Russian: Московский патриархат, romanized: Moskovskiy patriarkhat), is an autocephalous Eastern Orthodox Christian church. It has 194 dioceses inside Russia. The primate of the ROC is the patriarch of Moscow and all Rus'.

The history of the ROC begins with the Christianization of Kievan Rus', which commenced in 988 with the baptism of Vladimir the Great and his subjects by the clergy of the ecumenical patriarch of Constantinople. Starting in the 14th century, Moscow served as the primary residence of the Russian metropolitan. The ROC declared autocephaly in 1448 when it elected its own metropolitan. In 1589, the metropolitan was elevated to the position of patriarch with the consent of Constantinople. In the mid-17th century, a series of reforms led to a schism in the Russian Church, as the Old Believers opposed the changes.

Vladimir I Sviatoslavich or Volodymyr I Sviatoslavych (Old East Slavic: Володимѣръ Свѧтославичь, romanized: Volodiměr Svętoslavič; Christian name: Basil; c. 958 – 15 July 1015), given the epithet "the Great", was Prince of Novgorod from 970 and Grand Prince of Kiev from 978 until his death in 1015. The Catholic Church and the Eastern Orthodox Church both canonised him as Saint Vladimir.

Vladimir's father was Sviatoslav I of the Rurik dynasty. After the death of his father in 972, Vladimir, who was then the prince of Novgorod, was forced to flee abroad after his brother Yaropolk murdered his other brother Oleg in 977 to become the sole ruler of Rus'. Vladimir assembled a Varangian army and returned to depose Yaropolk in 978. By 980, Vladimir had consolidated his realm to the Baltic Sea and solidified the frontiers against incursions of Bulgarians, Baltic tribes and Eastern nomads. Originally a follower of Slavic paganism, Vladimir converted to Christianity in 988, and Christianized the Kievan Rus.

The history of Russia begins with the histories of the East Slavs. The traditional start date of specifically Russian history is the establishment of the Rus' state in the north in the year 862, ruled by Varangians. In 882, Prince Oleg of Novgorod seized Kiev, uniting the northern and southern lands of the Eastern Slavs under one authority, moving the governance center to Kiev by the end of the 10th century, and maintaining northern and southern parts with significant autonomy from each other. The state adopted Christianity from the Byzantine Empire in 988, beginning the synthesis of Byzantine, Slavic and Scandinavian cultures that defined Russian culture for the next millennium. Kievan Rus' ultimately disintegrated as a state due to the Mongol invasions in 1237–1240. After the 13th century, Moscow emerged as a significant political and cultural force, driving the unification of Russian territories. By the end of the 15th century, many of the petty principalities around Moscow had been united with the Grand Duchy of Moscow, which took full control of its own sovereignty under Ivan the Great.

Ivan the Terrible transformed the Grand Duchy into the Tsardom of Russia in 1547. However, the death of Ivan's son Feodor I without issue in 1598 created a succession crisis and led Russia into a period of chaos and civil war known as the Time of Troubles, ending with the coronation of Michael Romanov as the first Tsar of the Romanov dynasty in 1613. During the rest of the seventeenth century, Russia completed the exploration and conquest of Siberia, claiming lands as far as the Pacific Ocean by the end of the century. Domestically, Russia faced numerous uprisings of the various ethnic groups under their control, as exemplified by the Cossack leader Stenka Razin, who led a revolt in 1670–1671. In 1721, in the wake of the Great Northern War, Tsar Peter the Great renamed the state as the Russian Empire; he is also noted for establishing St. Petersburg as the new capital of his Empire, and for his introducing Western European culture to Russia. In 1762, Russia came under the control of Catherine the Great, who continued the westernizing policies of Peter the Great, and ushered in the era of the Russian Enlightenment. Catherine's grandson, Alexander I, repulsed an invasion by the French Emperor Napoleon, leading Russia into the status of one of the great powers.