Robert Harron

Born in New York City, Harron was second oldest child of nine siblings in a poor, working-class Irish Catholic family. Harron's younger siblings John (nicknamed "Johnnie"), Mary, and Charles also became actors while one of his younger sisters, Tessie, was an extra in silent films. Charles was killed in a car accident in December 1915. Tessie died of Spanish influenza in 1918 while Harron's brother John died of spinal meningitis in 1939.

Harron attended the Saint John Parochial School in Greenwich Village. At the age of fourteen, he found work as an errand boy at American Biograph Studios near Union Square in Manhattan to help support his family. In addition to cleaning duties, Harron also appeared as an extra in a few shorts for Biograph. Within a year of working for Biograph, Harron was noticed by newly hired director D.W. Griffith. Harron quickly became a favorite of Griffith, and Griffith began to give the 14-year-old increasingly larger film roles. His first film for Griffith was the 1908 comedy A Calamitous Elopement. (He fit the delivery boy costume and was repeatedly used in such roles until he outgrew the outfit.) The teenaged Harron was often cast by Griffith in the role of the "sensitive" and "naïve" boy, who was overwhelmingly sympathetic and appealing to American film-goers in the very early years of American motion pictures and not far removed from Harron's real-life persona; Harron was often described as a quiet and soft-spoken youth. It was these traits that helped garner much public interest in the young actor, especially amongst young female fans. In 1912 alone, Harron appeared in nearly forty films at Biograph.

Harron is probably best recalled for his roles in the three epic Griffith films: 1914's Judith of Bethulia, opposite Blanche Sweet, Mae Marsh, Henry B. Walthall, and Dorothy and Lillian Gish; 1915's controversial all-star cast The Birth of a Nation; and 1916's colossal multi-scenario Intolerance opposite such popular stars of the era as Lillian Gish, Mae Marsh, Miriam Cooper, Wallace Reid, Harold Lockwood and Mildred Harris. One of Harron's most popular roles of the era came in 1919 when he starred opposite Lillian Gish in the Griffith directed romantic film True Heart Susie.

Harron's film career continued to flourish throughout the 1910s, and he was occasionally paired with leading actresses Mae Marsh and Lillian Gish with romantic plots, often in roles that cemented his "sensitive boy" image. Harron had, in fact, a burgeoning off-screen romantic relationship with Dorothy Gish. By 1920, Harron had grown too old to continue playing the juvenile roles that had launched his career. He began losing leading man roles to Richard Barthelmess. Later that year, D.W. Griffith agreed to loan Harron to Metro Pictures for a four-picture deal. His first film for Metro, also the last film of his career, was the comedy Coincidence. The film was released in 1921, after Harron's death.