Edmund Fessenden Cobb was born to William Henry Cobb and Eddie Ross, and was the grandson of Edmund Gibson Ross, a notable figure in American politics. His parents ran a photography studio in Albuquerque, New Mexico, where some of Edmund's childhood photos are archived at the Museum of New Mexico, Palace of the Governors.
Edmund had two sisters, Susan Ross Cobb and Daphne M. Cobb, and a brother, Wilfred B. Cobb. His career in the film industry spanned over five decades, from 1910 to 1965, and was documented in a book by Kalton C. Lahue, Winners of the West: Sagebrush Heroes of the Silent Screen.
Edmund married his first wife, Helen Hayes, in 1914, and they had a daughter, Eddie Marie Cobb. The couple appeared together in several films, including A Rodeo Mixup and Riders of the Range. They divorced in the 1920s and both remarried.
Helen Hayes married her second husband, Edwin Jackson, in 1930, and passed away around 1932. Edmund married his second wife, Vivian Marie Winter, in 1934, and they remained together until her death in 1974.
Edmund Cobb died just twenty days after Vivian, on August 15, 1974, at the Motion Picture and Television Hospital.