Russian tragic actor with a Byronic flair who relied principally upon inspiration and intuition to lend force to his performances.

The son of Stepan Fedorovich Mochalov, a prominent actor, he made his debut in 1817 to immediate acclaim. Although he essayed a few comic roles, such as Almaviva in Pierre Beaumarchais' Barber of Seville, his forte was distinctly that of the tragedian. Mochalov was especially successful playing the heroes of Friedrich Schiller's Don Carlos, The Robbers, Cabal and Love, and Maria Stuart; he was equally well received in a wide range of Shakespearean parts, including the title roles of Richard III, Othello, King Lear, Coriolanus, and Hamlet. He is credited with being the first Russian to insist upon Russian translations of Shakespeare based on the original English texts rather than on French versions.

The preponderance of Mochalov's career was spent at Moscow's Maly Theatre, and he was invariably compared to his St. Petersburg rival, Vasily Karatygin (1802–53). Where Mochalov enacted emotional tirades and temperamental passions, Karatygin reflected studied subtleties and calculated effects; where Mochalov was intuitive, active, and resounding, Karatygin was technical, poised, and resonant. Between the two, they established the limits from which M.S. Shchepkin and P.M. Sadovsky would synthesize the basis for Russian realism in acting. Unfortunately, Mochalov's romanticism, relying as it did upon energies created by the inspiration of the instant, tended to make his performances somewhat uneven.