Nanook of the North (1924) is of the world's greatest documentaries, made by the man generally considered to be the "father" of the documentary, Robert Flaherty. It's a masterful film made by someone who was relatively unschooled in filmmaking. But Flaherty spent a long time with Nanook and his family (close to a year, I think), and in that time managed exquisitely to capture the the lives of the Inuit in their starkly beautiful world. And I don't think it was "staged," except perhaps for a few attempts at overlapping actions for continuity's sake - but I'd question even that. I think it's what it appears to be: a credible and powerfully authentic documentary. One sad footnote: Nanook died of starvation soon after the film’s completion.
As for the question of the documentary category itself: it seems to me that it's becoming more and more blurred in present days.
The Story of the Weeping Camel (2003) won an Oscar as best documentary even though it seemed to me to be a perfect blend of both documentary and narrative elements. The same filmmaker's next film,
The Cave of the Yellow Dog (2005), is very similar. But in the end, I'm happy for the final result, whatever hybrid it may be called, because both films are wonderful to watch.
Perhaps it's the ethnographic approach that skews the genre slightly. There's a wonderful silent film,
The Silent Enemy (1930), an obvious and acknowledged "docu-drama" of Canadian Indians at war with each other that may be close to Nanook. And I would agree that none of these films is at all like Barbara Kopple's
Harlan County, U.S.A. or any number of other conventional documentaries. But clearly, they're not just narrative films either.
And where, I wonder, do the more abstract and poetic (nefarious propaganda aside) films like Refienstahl's
Olympia or
Triumph of the Will and Eisentein's
October (Ten Days That Shook the World) or
Strike belong? They're clearly documentaries but are also not at all like the works of Kopple, the Maysles Brothers, Claude Lanzman, Michael Apted, Werner Herzog, Ken Burns, et al. Interesting topic to ponder.