The great moments of revolutionary history have all been enormous popular festivals - the storming of the Bastille, the uprisings of 1848, the Paris Commune, the revolutions of 1917-9, Paris '68. Conversely, popular festivities have always been looked on by the authorities as a problem, whether they have banned, tolerated or semi- institutionalised them. Why does power fear free celebration? Could it be something to do with the utopian urges which seize a crowd becoming aware of its own power? From the middle ages onwards the carnival has offered glimpses of the world turned upside down, a topsy turvy universe free of toil, suffering and inequality.