"Jack" O'Brien (December 13, 1884 – August 15, 1936) was an American actor and film director of the silent era.

[2] However, Daniel Frohman persuaded him to change his mind and try a stage career instead.

[2] He performed as a juvenile lead for the Augustus Thomas Company, beginning with the play Alabama,[1] and later for Essanay Studios.

[2] He also worked as a cameraman for Broncho Billy Anderson and wrote scenarios for Essanay.

[6]) Some sources state he worked on D. W. Griffith's ground-breaking epic The Birth of a Nation.