Ivan Ilyich Sergiev (1829-1908), known to his contemporaries as Fr. John of Kronstadt, was the most revered figure of the Orthodox Church of Russia in the half-century leading up to the Bolshevik revolution of 1917. In 1964, the Russian Orthodox Church outside Russia formally glorified him as a Saint. St. John of Kronstadt is best known through his spiritual journal My Life in Christ, which has been read by millions.