In 1899 Edwin Stanton Porter joined the Edison Manufacturing Company. Soon afterward he took charge of motion picture production at Edison's New York studios, operating the camera, directing the actors, and assembling the final print. During the next decade he became the most influential filmmaker in the United States. From his experience as a touring projectionist Porter knew what pleased crowds, and he began by making trick films and comedies for Edison. One of his early films was Terrible Teddy, the Grizzly King, a satire made in February 1901 about the then Vice President-elect, Theodore Roosevelt. Like all early filmmakers, he took ideas from others, but rather than simply copying films he tried to improve on what he borrowed. In his Jack and the Beanstalk (1902) and Life of an American Fireman (1903) he followed earlier films by France's Georges Méliès and members of England's "Brighton School", such as James Williamson. Instead of using abrupt splices or cuts between shots, however, Porter created dissolves, gradual transitions from one image to another. In Life of an American Fireman particularly, the technique helped audiences follow complex outdoor movement.
In his next and most important film, The Great Train Robbery (1903), Porter took the archetypal American Western story, already familiar to audiences from dime novels and stage melodrama, and made it an entirely new visual experience. The one-reel film, with a running time of twelve minutes, was assembled in twenty separate shots, along with a startling close-up of a bandit firing at the camera. It used as many as ten different indoor and outdoor locations and was groundbreaking in its use of "cross-cutting" in editing to show simultaneous action in different places. No earlier film had created such swift movement or variety of scene. The Great Train Robbery was enormously popular. For several years it toured throughout the United States, and in 1905 it was the premier attraction at the first nickelodeon. Its success firmly established motion pictures as commercial entertainment in the United States.