19. Woody Allen
Woody Allen's films are so unique in American cinema, focusing more on characters, intellectual concepts, and theories about art, movies, and life, that it's almost impossible to classify his films. While his films are all comedies to some extent, the dark humor that he brings and his cynical outlook on life gives them a bit of a tragic bent as well. Even so, few American directors have ever been more blatantly enjoyable for as long as Allen as he continues to turn out a movie year after year, with this year's Blue Jasmine already earning considerable acclaim. An unmatched screenwriter, Woody Allen has received more screenplay nominations at the Oscars than any other filmmaker, despite his refusal to accept or acknowledge his wins publicly. Although his films are always very identifiable as a "Woody Allen film", they have run the gamut of styles during his career from his early slapstick comedies to his sophisticated, mainstream comedies of the late 70's and early 80's to the dark dramas he has occasionally turned out in his later career. Although he is one of the most inconsistent of all great directors in terms of quality, making a film every year ensures that he has had his share of flops, Allen has created one of the most unique filmographies of any American filmmaker. His influence might be more keenly felt in terms of screenwriting, but his overall career, longevity, and reputation in the film industry are more than enough to earn him a place on this list.