But if the Harlem of the Twenties and Thirties has come to London for the exhibition and its related series of talks and events, one of the show's most striking features is the light it throws on how London, and Europe generally, reacted to the revolution in literature, music and the visual arts that the movement of the Harlem Renaissance represented. For Powell: "In the past, we've had a tendency to look at it as something peculiar to Harlem and to one decade, and as something very isolated in terms of just affecting and dealing with black people. But that is incorrect. In truth, it was a global phenomenon that touched not just Harlem but New York, and not just New York but most of the urban centres of the USA. It also pops up in places like London, through people like Edward Burra, and in Jamaica, through people like Edna Manley, and in Paris too. So with this show there was an opportunity to rethink and look back at that moment, and to realise the international dimension of it, and also the inter-cultural and inter-racial dimensions of what we're talking about."
The reactions of Europeans to the experience of Harlem are a perfect illustration of how social constructions of black America were hidebound by conflicting impulses that both celebrate and denigrate their subject, and by a voyeurism that can still be detected in Robert Mapplethorpe's photographs of black models in the Seventies and Eighties, and even in the everyday treatment of black artists in the media today (the recent film Basquiat comes to mind). The camp-realist painter Burra - who is represented in the exhibition - lived in New York in 1933, and for him, Harlem was a typically eccentric liberation, "like Walham Green gone crazy". He wrote (in his usual breathless style, for he had never gone to school) to his friend William Chappell, the dancer, of a cabaret where one of the chief attractions was " `Gloria Swanson', a mountainous coal-black nigger in a crepe de Chine dress trimmed with sequins who rushed about screaming Clappy weather, just can't keep my old arse together keeps runnin' all the time etc and rush up to the table dragging his sequins up and disclosing a filthy pair of pink silk panties how he managed I don't know no balls or anything as far as I could see."
Writers like Ronald Firbank, who wrote the Caribbean fantasy Prancing Nigger in 1925, Evelyn Waugh - who included the character of the jazz musician Chokey in Decline and Fall of 1929 - and the American Carl Van Vechten, who published Nigger Heaven in 1926 (and whose photographs are included in the show), focused on elements of black life in ways that vacillated between the twin poles of modernity and primitivism that have come to characterise white approaches to black culture ever since, from Louis Armstrong to gangsta rap. Indeed, jazz was seen simultaneously as both impeccably modern - the perfect Futurist noise-music - and irretrievably primitive, a construction reinforced constantly by the jungle imagery of sheet-music illustrations and set backdrops. But while Osbert Sitwell and Noel Coward cruised the fashionable Harlem salon hosted by the black heiress to a hair-straightening fortune, posh rebel Nancy Cunard published (in 1934) the remarkable anthology Negro, which set the writings of many of the Harlem poets alongside an article on Kenya by the young Jomo Kenyatta, and a cover designed by Henry Matisse.
For the Spanish poet and playwright Garcia Lorca, who visited New York in 1929, "The Negro, spilling music out of his pockets" was the most arresting feature of the city. He wrote that: "Apart from the art of the Negro, the United States has nothing to show but machines and automatons." Interestingly, the machines and automatons are as much a part of the visual culture of the Harlem Renaissance as seen in the exhibition as the echoes of an imagined "primitive" African past. The wonderful paintings of Aaron Douglas mix strong motifs of African life with the Depression-moderne style of Cubist- derived art deco, and the portrait of poet Langston Hughes by the emigre German artist Winold Reiss places the subject against a stylised background of tenements and musical notes. Elsewhere, Reiss's ink drawings of Harlem street life set sharply dressed gents next to Egyptian-headed goddesses amid an Expressionist tumble of chimney stacks and night-lit interiors. "The Ascent of Ethiopia" by Lois Mailou Jones contrasts the Nubian figure in the foreground against an orphic design of scrycrapers and symbols of the contemporary arts. The paintings of Archibald J Motley - who for many will be the star of the show - take the human comedy of Harlem life as their subject, treating holy rollers, bar-room conspirators and blues dancers with livid colour, and the compositional exactitude of a black Balthus.
The amazing `"Toussaint L'Ouverture Series" of guaches by the 19-year- old Jacob Lawrence is in a class of its own, however, so idiosyncratic as to be quite beyond compare. Now aged 80, Lawrence is the most famous black painter in America, and though rather frail, he will be at the South Bank today, in the Purcell Room at 2pm, to talk about his work with Richard Powell. Though the series dates from 1937-38, at what most people see as the tail-end of the Renaissance, it acts as a powerful tribute to the importance the movement had in helping to rediscover black history for a new generation. Though the impact of poets like Langston Hughes and Countee Cullen lessened after the great Depression and the literary and political feuds of the time, their examples - and their failings - eventually formed the basis for the radical black arts movement of the Sixties.
For the British actor Burt Caesar, who tomorrow at 6pm appears in a dramatised reading entitled "The Dark Tower", the Harlem Renaissance was a secret history, "Something I had to discover for myself, over the last 20 years since I was a student. It was a history which, like a river - which is one of the great metaphors in the poetry of the movement - had gone underground; no one could see it; no one could hear it, and it took someone like Alice Walker - who was popular - to rediscover it from the perspective of the black power era though her labyrinthine detective work in searching out the life of Zora Neale Hurston."
For Caesar, the black British experience of today is: "Not so much a Renaissance as a nascence. It's really coming fresh from the first generation of black artists either born here or having spent most of their lives here. It's like the children of Africans, who are now Londoners, or from Birmingham or Manchester, and who speak as cockneys or whatever, and it's perhaps most marked among the children of the south Asian community with their break from the religious past. There really is something new and fresh. Who knows how long it will last?" The Hayward exhibition provides a wonderful window on to a world that, while it vanished long ago, will be instantly recognisable to any student of rap, jazz or soul album covers. It is educational in the very best sense, and it should definitely be seen, Sade notwithstanding.
`Rhapsodies in Black: Art of the Harlem Renaissance' to 17 Aug, Hayward Gallery, SBC, London SE1: 0171-928 3144; recorded information: 0171-261 0127; `The Norton Anthology: African-American literature' edited by Henry Louis Gates Jr and Nelly McKay published by WW Norton, provides an exhaustive survey of Harlem Renaissance literature