In 1909, he went to Florence to study singing with Vincenzo Lombardi and made his operatic debut in May 1911 in Fossombrone as Marcello in La bohème.

His first appearance in the United States was as Jack Rance in The Girl of the Golden West with Henry Wilson Savage's English Grand Opera Company.

[3] His many stage roles included several Broadway premieres such as Landolfo in Pirandello's The Living Mask (Henry IV), 1924; Doctor Schindler in Schnitzler's The Call of Life (Der Ruf des Lebens), 1925; Captain Adam Brant in O'Neill's Mourning Becomes Electra, 1931; Ben Loman in Miller's Death of a Salesman, 1949; and Richard Bravo in Maxwell Anderson's The Bad Seed, 1954.

Chalmers also produced and directed several short comedy films written by Robert Benchley, including The Sex Life of the Polyp and The Treasurer's Report, both released in 1928.

[5] His voice can be heard as the narrator in two documentary films by Pare Lorentz, The Plow That Broke the Plains (1936) and The River (1938), both with scores by Virgil Thomson.