Film: You said you wanted a revolution...

How deep was French cinema's contribution to the events of 1968?

The interior of London's French Institute has taken on the trappings of a May 1968 theme park, elegant lobby strung with banners emblazoned with period slogans. Rather touchingly, little piles of sand and paving stones are scattered about, alluding to one of those slogans - "sous les pavees, la plage" (underneath the street, the beach). But there is something almost indecent in the fact that this institution - the very embodiment of Establishment France in London - should take on the memory of '68 and render it so cosy. After all, nobody's going to start lobbing paving stones in elegant South Kensington, are they?

Thirty years on from May '68 and it's possible for this kind of radical- chic nostalgia to predominate. Few can remember what May '68 was like, or even what it was about exactly, but the images of the period continue to exert a profoundly romantic pull. It is significant, then, that two of London's most adventurous cinemas should devote separate but overlapping seasons to films of the period (French Institute, 20 May-2 June/Lux: 14 May-24 June). It's not just that the French cinema produced films about what became known as les evenements de mai, so much as cinema was part of the events. Film-makers took to the spirit of May, as much as students and factory workers.

There are two key events in the French cinema's own involvement. In February 1968, French film-makers had been radicalised by the Minister of Culture's authoritarian handling of Henri Langlois, who had been summarily dismissed as the director of the Cinematheque Francaise. It was here, most famously, that the directors of the French new wave came to absorb the diet of films that Langlois showed. He was their Godfather and they sprang to his defence. Events ran to a fracas with the police, and disputes with the minister, Andre Malraux, the former radical icon who himself had made L'Espoir, a film about the Spanish Civil War in 1939. When, on May 20, the Cannes Festival was halted in sympathy with the demonstrators, film makers drew up plans for a radical reorganisation of the entire business of cinema, root and branch while also throwing themselves into direct action.

There was a real and pressing need for film crews to be out on the streets and at the barricades. The film-makers were involved in covering the events as they unfolded and were allotted specific areas in which to shoot. The American documentarist, William Klein, was living in Paris at the time. "Around 18 May, some students from the Sorbonne came to ask for a film crew, I put myself up for it." Klein was involved with the loose association of film-makers that had called itself, with self-conscious reference to Republican tradition, the Etats Generaux du cinema. "The project that emerged was to do a series of shoots in factories, farms and university faculties. Each team had its sector ... ours was the Latin Quarter," Klein explains. For ten days and nights, Klein and his crew were in the thick of it, feverishly gathering material for a vast collective film on the events which, fittingly enough, never happened. Klein's own cut of this footage has finally been edited into a film, never screened before in the UK, Grands soirs et Petits matins (French Institute, 26 May, 6pm).

May '68 seems to have been like a clusterbomb of images,throwing footage out to get caught by history. Much in keeping with the events themselves, the particles of documentary films produced have come to exercise an intense fascination for French film-makers. During May '68, they subsumed themselves in producing "cine-tracts". Polemical and didactic in intent, they also became unique historical documents. Big time directors such as Jean-Luc Godard and Chris Marker, made their own, anonymous contributions. Their 'anonymity' was a gesture, the 'nom d'auteur' was temporarily jettisoned as simply being a capitalist marketing tool.

One film, shot by film students during a strike at a factory in Saint Ouen, struck the French documentarist Herve Le Roux so deeply that he made a film that tracked down those caught on strike and on camera. Le Roux's film, Reprise, is a personal, multi-perspective take on the moment of May '68, that returns obsessively to the short militant film that inspired it. In Reprise, Le Roux is preoccupied with the memory (and forgetting) of the events of '68. "In the 80s ... this memory, which had been passed from generation to generation, was broken," he explains. "The news reports we receive now about the problems of the suburbs, about strikes and unemployment are not grounded in this memory."

Roux sounds a warning that the idea of May '68 as a political act has faded from the memory, even as its images proliferate. That said, the French media went to town for the 30th anniversary. Le Monde published a 44-page supplement reproducing its coverage and the student newspaper, L'Echo de l'actualite, chipped in extensive coverage.

Perhaps more tellingly, last year saw mass demonstrations in France against harsh new immigration laws. An initial petition protesting against the laws had been organised by a group of young film-makers. This acted to mobilise opinion and rapidly became a barometer of national attitude. Some were demonstrating, they claimed, against the "Le Pen-isation of minds" that they detected in the mainstream right-wing's political handling of the immigration issue. It became very clear that, on immigration, France was split - not just on race but equally on class. The momentary unity of worker and student in '68 looked irretrievably lost.

With the demonstrations of '68 came a sense of liberation extending to areas of cultural and sexual politics. The Situationist International produced in 1967 a book, The Society of the Spectacle, that described a media-saturated world of over-consumption. It was stark, incendiary reading and the Situationists gained a reputation as gnomic culture-pranksters. Their leading light, Guy Debord, author of The Society of the Spectacle, could be said to be the spiritual father of Jean Baudrillard and Malcolm McLaren.

Soon after '68, films started to appear that viewed France from the other side of "the events". Godard's broad, Brechtian star-vehicle of 1972, Tout va bien, with Jane Fonda and Yves Montand, continued with the political polemic. Jean Eustache's emotionally harrowing La Maman et la putain (1972) looked at "the crack that opened in reality" from the perspective of sexual politics. "Take your imagination for reality", proclaims one of the archetypal slogans of May '68 - which should be every film-maker's first commandment.

The Lux Cinema, Hoxton Square 0171 684 0201; The French Institute 0171 838 2144.