What the filmmaker didn't envision was how epic his odyssey would become. When his producer, John Archer, suggested making the film, Cousins told him a three-hour documentary was needed to do his 'story' justice. Six years later, it is released as a cultural juggernaut.

It traces the development of cinema across time (from Louis Le Prince's 1888 piece, Traffic Crossing Leeds Bridge, to Christopher Nolan's Inception of 2010) and geographical space (from the Hollywood studios to rural Iran, and from Parisian boulevards to Tiananmen Square in Beijing, via congested roundabouts in Dakar) - complete with snippets of more than 1,000 films and rarely seen footage of filmmakers in action as well as of the social turmoil from which their work emerged.

Through its 15 hour-long segments, the film places the US and Europe as the first cradles of institutionalised filmmaking, before the narrative shifts to Asia, South America and Africa from the 1950s onwards, as Cousins traces his story with thoughtful juxtaposition of examples from around the world.

Cousins manages to show how filmmakers take cues from their predecessors. Carol Reed's use of a character imagining a face out of the froth in his coffee (in Odd Man Out) is appropriated by Jean-Luc Godard (in the famous cosmos-in-a-cup shot in Two or Three Things I Know About Her), and Martin Scorsese (in Taxi Driver) channels Travis Bickle's volatile inner self through a close-up of an Alka-Seltzer dissolving in a glass of water).

Chinese-language cinema features prominently in Cousins' film as he goes beyond the usual landmarks of Bruce Lee and directors John Woo Yu-sum, Wong Kar-wai and Zhang Yimou.

'I must say one of the memorable things was meeting Xie Jin,' he says, referring to the late director who was persecuted by the Red Guards in the 1960s because of the 'reactionary elements' in his 1965 film, Two Stage Sisters (a clip is shown in The Story of Film, screened earlier at this year's Hong Kong International Film Festival). '[He bears] all that trauma and the scars of the Cultural Revolution. It was astonishing he didn't compromise under all that ... he had lost his memory somewhat when I met him, but he represented Chinese cinema and the extraordinary times before the Cultural Revolution. And it was fascinating to me to meet a man who went that far back, who saw the Ruan Lingyu films when they first came out,' Cousins says.

He has devoted considerable screen time to the 1930s Chinese film icon too. Apart from visiting Ruan's grave and the Chinese Film Archive to do research on her work, he also went to the Great Wall of China with Maggie Cheung Man-yuk - who played Ruan in Stanley Kwan Kam-pang's Ruan biopic, Centre Stage.

Because his book cited examples from around the world, Cousins flew around the world to visit the places where those films were made and to talk to filmmakers about the significance of the classics mentioned in his compendium.

'I was writing a book for my 15-year-old self - that was when I read The Story of Art by E.H. Gombrich,' says Cousins. 'And what I liked about it was that it didn't have that much jargon, and it had certain narratives [in its charting of the history of art]. It was like a tasting menu, as it gave you flavours of different things.

'But it wasn't great on Eastern art. So I thought, wouldn't it be great if there was such a book for cinema, a single volume which is accessible and passionately international, a history of cinema which doesn't make the same mistakes as many other 'histories' had, written by white people in the West who don't know too much about African or Asian cinema? And when I was writing the book I kept thinking, if only I could show people this clip of Casablanca or A Touch of Zen instead of just writing about it. So the film is a dream come true.'

Born and raised in Northern Ireland, Cousins says his engagement with left-field cinema came quite late in life. 'I came from a very working-class background, so there was no idea of cultural or artistic cinema then - it was not available to me in my world,' he recalls. He says he didn't discover so-called 'world cinema' until he was 19, when he was preparing to study film, media studies and fine art at the University of Stirling in Scotland. The experience of 'seeing everything' informed his budding career as a filmmaker, and in 1991 he joined the Edinburgh Film Festival as a programmer before becoming its director.

Leaving the festival five years later, he divided his time between presenting film programmes on television, writing books, teaching cinema courses, directing documentaries, running other festivals (such as Cinema China, a showcase which toured 20 British cities in 2007), and running a charity called Scottish Kids Are Making Movies, which aims to encourage teenagers to 'think creatively about film'.

It's an initiative that reflects Cousins' efforts to bring films, complete with their visceral magic and their intellectual contexts, closer to the audience. In 2008, he and actress Tilda Swinton organised a film festival in the small town of Nairn, where audiences watched movies while seated on bean-bags. The next year, they put together a travelling festival in which a truck carrying a portable film screen was hauled, by the pair plus a team of fellow cinephiles, across the Scottish Highlands to bring films to audiences living in the more remote parts of the region.

'Tilda and I have a word which we often use: 're-enchant'. Some multiplexes might be good, but they are basic architectural voids with no sense of humanity. We'd like to make something more magical of the film-going experience, so what we'd like to do is to take the idea of a festival and mash it up with other ideas, like a children's party or rave culture [Cousins recorded a drum'n'bass track inspired by Jean Eustache's La Maman et la Putain in 2004],' Cousins says. 'We made a real physical effort to show our love of films, which is our religion.'

His latest project is another pilgrimage. What is This Film Called Love? - with a soundtrack by P.J. Harvey and Simon Fisher Turner - is a road movie-style documentary about walking, a process which allows people to 'remember things more and think more'.

And so he's working at home rather than attending premieres at Cannes. Contemplation of cinema now takes precedent over joining the media scrum on the Croisette, as his Story of Film has proved.