Nicholas I, 1796–1855, czar of Russia (1825–55), third son of Paul I. His brother and predecessor, Alexander I, died childless (1825). Constantine, Paul's second son, was next in succession but had secretly renounced (1822) the throne after marrying a Polish aristocrat. This secrecy resulted in confusion at Alexander's death and touched off the Decembrist uprising, a rebellion against Nicholas, which he crushed on the first day of his reign.
Nicholas strove to serve his country's best interests as he saw them, but his methods were dictatorial, paternalistic, and often inadequate. One important achievement, however, was the codification (1832–33) of existing Russian law. A few measures attempted to limit the landlords' powers over their serfs, and the condition of peasants belonging to the state was improved. Industry progressed somewhat; the first Russian railroad was completed in 1838. Efforts were made to stabilize the ruble and reduce the growing national debt.
The motto "autocracy, orthodoxy, and nationality," expressing the principles applied to a new system of education, was also used by Nicholas in suppressing liberal thought, controlling the universities, increasing censorship, persecuting religious and national minorities, and strengthening the secret police. Intellectual life was in ferment, the revolutionary movement took form, and the two schools of thought held by Slavophiles and Westernizers emerged. With Pushkin, Lermontov, and Gogol a golden age in literature began.
Under Nicholas, Russia gained control of part of Armenia and the Caspian Sea after a war with Persia (1826–28). A war with the Ottoman Empire (1828–29; see Russo-Turkish Wars) gave Russia the eastern coast of the Black Sea and the mouth of the Danube. Nicholas brutally suppressed the uprising (1830–31) in Poland and abrogated the Polish constitution and Polish autonomy. In 1849 he helped Austria crush the revolution in Hungary. His attempts to dominate the Ottoman Empire led to the disastrous Crimean War (1853–56). He was succeeded by his son Alexander II.
See biographies by B. W. Lincoln (1978) and A. E. Presniakov (1978); P. Kurth, Tsar (1995).