This introduction to The Road to Happiness (1924) explains how the producers used Fairfax County, Virginia, as the location but used a different name in the film so that the real county would remain anonymous. Real people that lived in Fairfax County are featured in the film. You can view the introduction video here. Also, the full version of The Road to Happiness is available here.
Vault217
George Mason University Libraries' Special Collections Research Center Blog