A
For much of the twentieth century, documentary films were overshadowed by their more successful Hollywood counterparts. For a number of reasons, documentaries were frequently ignored by critics and film studies courses at universities. Firstly, the very idea of a documentary film made some people suspicious. As the critic Dr Helmut Fischer put it, ‘Documentary makers might have ambitions to tell the “truth” and show only “facts” but there is no such thing as a non-fiction film. That’s because, as soon as you record an incident on camera, you are altering its reality in a fundamental way’. Secondly, even supporters of documentaries could not agree on a precise definition, which did little to improve the reputation of the genre. Lastly, there were also concerns about the ethics of filming subjects without their consent, which is a necessity in many documentary films.

B
None of this prevented documentaries from being produced, though exactly when the process started is open to question. It is often claimed that Nanook of the North was the first documentary. Made by the American filmmaker Robert J. Flaherty in 1922, the film depicts the hard, sometimes heroic lives of native American peoples in the Canadian Arctic. Nanook of the North is said to have set off a trend that continued through the 1920s with the films of .Dziga Vertov in the Soviet Union and works by other filmmakers around the world. However, that 1922 starting point has been disputed by supporters of an earlier date. Among this group is film historian Anthony Berwick, who argues that the genre can be traced back as early as 1895, when similar films started to appear, including newsreels, scientific films and accounts of journeys of exploration.

C
In the years following 1922, one particular style of documentary started to appear.These films adopted a serious tone while depicting the lives of actual people. Cameras were mounted on tripods and subjects rehearsed and repeated activities for the purposes of the film. British filmmaker John Grierson was an important member of this group. Grierson’s career lasted nearly 40 years, beginning with Drifters ( 1929) and culminating with I Remember, I Remember I 1968). However, by the 1960s Grierson’s style of film was being rejected by the Direct Cinema movement, which wanted to produce more natural and authentic films: cameras were hand-held; no additional lighting or sound was used; and the subjects did not rehearse. According to film writer Paula Murphy, the principles and methods of Direct Cinema brought documentaries to the attention of universities and film historians as never before. Documentaries started to be recognised as a distinct genre worthy of serious scholarly analysis.

D
Starting in the 1980s, the widespread availability of first video and then digital cameras transformed filmmaking. The flexibility and low cost of these devices meant that anyone could now be a filmmaker. Amateurs working from home could compete with professionals in ways never possible before.The appearance of online film­ sharing platforms in the early 2000s only increased the new possibilities for amateur filmmakers. Nonetheless, while countless amateur documentaries were being made, perhaps the most popular documentary of 2006 was still the professionally made An Inconvenient Truth. New cameras and digital platforms revolutionised the making of films. But as critic Maria Fiala has pointed out, ‘The argument sometimes put forward that these innovations immediately transformed what the public expected to see in a documentary isn’t entirely accurate.’