Which film is considered the first feature-length narrative film?

"The Story of the Kelly Gang" (1906) is considered the first feature-length narrative film primarily because it was one of the first films to exceed the one-hour mark in runtime, thus establishing a new standard for film length and narrative depth. This Australian film tells a semi-fictionalized account of the life of the infamous outlaw Ned Kelly and his gang.

At the time of its release, most films were short, typically lasting around 10-15 minutes. "The Story of the Kelly Gang" broke this trend by presenting a structured narrative that unfolded over an extended period, allowing for character development and a more complex storytelling approach, which helped to elevate film as a serious artistic medium.

While "The Great Train Robbery" (1903) is notable for its innovative storytelling and action sequences, it remains a short film. Similarly, while "Birth of a Nation" (1915) and "Intolerance" (1916) are significant for their respective cultural impacts and storytelling techniques, they were released after "The Story of the Kelly Gang" and therefore are not considered the first feature-length films in history.