Tradition says the Viking Rurik came to Russia in 862 and founded the first Russian dynasty in Novgorod. The various tribes were united by the spread of Christianity in the 10th and 11th centuries; Vladimir “the Saint” was converted in 988. During the 11th century, the grand dukes of Kiev held such centralizing power as existed. In 1240, Kiev was destroyed by the Mongols, and the Russian territory was split into numerous smaller dukedoms. Early dukes of Moscow extended their dominion over other Russian cities through their office of tribute collector for the Mongols and because of Moscow's role as an administrative and trade center.
In the late 15th century, Duke Ivan III acquired Novgorod and Tver and threw off the Mongol yoke. Ivan IV—the Terrible (1533–1584), first Muscovite czar—is considered to have founded the Russian state. He crushed the power of rival princes and boyars (great landowners), but Russia remained largely medieval until the reign of Peter the Great (1689–1725), grandson of the first Romanov czar, Michael (1613–1645). Peter made extensive reforms aimed at westernization and, through his defeat of Charles XII of Sweden at the Battle of Poltava in 1709, he extended Russia's boundaries to the west. Catherine the Great (1762–1796) continued Peter's westernization program and also expanded Russian territory, acquiring the Crimea, Ukraine, and part of Poland. During the reign of Alexander I (1801–1825), Napoléon's attempt to subdue Russia was defeated (1812–1813), and new territory was gained, including Finland (1809) and Bessarabia (1812). Alexander originated the Holy Alliance, which for a time crushed Europe's rising liberal movement.
Alexander II (1855–1881) pushed Russia's borders to the Pacific and into central Asia. Serfdom was abolished in 1861, but heavy restrictions were imposed on the emancipated class. Revolutionary strikes, following Russia's defeat in the war with Japan, forced Nicholas II (1894–1917) to grant a representative national body (Duma), elected by narrowly limited suffrage. It met for the first time in 1906 but had little influence on Nicholas.