Yakov Borisovich Knyazhnin (Russian: Я́ков Бори́сович Княжни́н, November 3, 1742 or 1740, Pskov – January 1, 1791, St Petersburg) was Russia's foremost tragic author during the reign of Catherine the Great. Knyazhnin's contemporaries hailed him as the true successor to his father-in-law Alexander Sumarokov, but posterity, in the words of Vladimir Nabokov, tended to view his tragedies and comedies as "awkwardly imitated from more or less worthless French models". Source: Wikipedia (en)