J. Hartley Manners, author of this sentimental, charming comedy, created a perennial vehicle for his wife, Laurette Taylor, who became one of the most beloved stage stars of the time in the title role. The bankrupt Chichesters are offered a financial reprieve if they will look after their orphaned cousin, teenager Peg, who arrives at the Chichester estate in time to catch her cousin Ethel in a secret tryst with Brant, a scheming philanderer. The snobby Chichesters look down on waif-like Peg, whose unfashionable clothes and beloved mutt appall them. Peg befriends a neighbor, Jerry, and manages to rescue Ethel from eloping with the nefarious Brant. When Jerry reveals himself as Peg's wealthy guardian, she wins approval of the Chichesters, her own riches, and Jerry's heart. Opening at the Cort Theatre on 20 December 1912, Manners's play and Taylor's touching performance won acclaim from critics and audiences, leading to an impressive 603 performances. Multiple tours, frequently with Taylor in the lead, popularized the play. A 1921 revival, starring Taylor, was as successful as the original production. Motion picture versions appeared in 1919, 1922 (starring Taylor), and 1933. Manners wrote the book for a 1924 musical version titled Peg O'My Dreams, but its quick demise did nothing to undermine the enduring popularity of Peg O'My Heart.
The Historical Dictionary of the American Theater. James Fisher.