Documentaries never had it so good. Believe it or not, before Y2K, they hardly ever played in theaters unless they were part of some government war propaganda, narrated by someone like Orson Welles or directed by Michael Moore. Occasionally, you caught one on PBS or had to watch one in school right? Now you can find them on the same bill with live action flicks, musicals and animated releases.
Nanook of the North, a 1922 release by Robert Flaherty, is considered the first commercially successful documentary film. Flaherty was criticized for staging some of the scenes depicting Inuit arctic life, but today even reality shows have writers.