Godunov, Boris (bərēsˈ gədōnôfˈ) [key], c.1551–1605, czar of Russia (1598–1605). A favorite of Ivan IV (Ivan the Terrible), he helped organize Ivan's social and administrative system. After Ivan's death (1584), Boris became virtual ruler of Russia, ostensibly as regent for Ivan's young son Feodor I, who was married to Boris's sister. Boris was popularly believed to have ordered the murder (1591) of Feodor's younger brother and heir, Dmitri, in order to secure the succession for himself. Upon Feodor's death (1598), an assembly of the ruling class chose Boris as czar. Under his rule the Russian church was recognized (1589) as an independent patriarchate, equal to other Eastern churches; peace was obtained with Poland and Sweden, and colonization of the southern steppes and W Siberia was spurred. Most important, Boris continued Ivan's policy of strengthening the power of state officials and townspeople at the expense of the boyars. Yet famine (1602–4) and popular distrust undermined his support, and when a pretender to the throne appeared claiming to be Feodor's brother Dmitri, many rallied to his support and he easily invaded Russia in 1604. Boris died, and his son, Feodor II, was unable to defend the throne against the false Dmitri. Boris's life is the subject of a drama by Pushkin that was the basis for Moussorgsky's famous opera.