Prince Petr Viazemskii (1792-1878), a close friend of Karamzin and Zhukovskii, Pushkin and Mickiewicz, was one of the most prominent poets of the Golden Age, a literary critic, diarist, translator, adviser to Aleksandr the First and Aleksandr the Second, and assistant to the minister of education. This is the first complete biography of this great personality, based on materials of the Ostaf"evo archive. Also available is his best known book of prose: his everyday notes.