actor, playwright, and manager of the Wallack Theatre Company, the training ground of virtually every important American stage performer of the 19th century.

Son of the actor-manager James William Wallack (Wallack, James William), Lester Wallack began his professional stage career by touring the English provinces; he made his New York debut in 1847. When his father took over the Lyceum Theatre in 1852 in New York City and renamed it the Wallack Theatre, Lester performed a number of comic and romantic parts with the company and worked also as stage manager until 1861, when he succeeded his father.

Under Lester Wallack, the theatre became famous for its polished productions of English plays and some new dramas, including his highly successful Rosedale (1863), in which he starred. The company included the actor James William Wallack II, Lester's cousin. In 1882 Lester opened a new Wallack Theatre and until his retirement five years later managed both playhouses. The new Wallack Theatre closed in 1915, but another Wallack playhouse flourished from 1924 to 1931. His Memories of Fifty Years was published in 1889.