Cultural movements are often said to flower or blossom: in the case of Art Nouveau, the sense is literal. This exuberant visual style wrapped its tendrils around all the major European cities between 1890 and 1910 - in particular Paris, Brussels, Vienna, Prague, Budapest, Munich, Glasgow, Turin, Helsinki, Moscow and Barcelona - and all genres, especially the decorative arts.
Known variously as Sezessionstil (Vienna), Jugendstil (Munich), stile floreale (Turin), Glasgow Style and modernisme (Barcelona), Art Nouveau had diverse origins and an eclectic range of references. It was a response to the giddy pace of social and technological change at the end of the 19th century: a conscious celebration of artifice, of all things modern, urban and international, exploiting newly available materials and combining elements of art, craft and design into a gesamtkuntswerk - a total work of art. From the sinuous metalwork of the Paris metro stations, to Aubrey Beardsley's illustrated prints for Wilde's Salome, from furniture to stained glass, sculpture to typography, the style became all pervasive in Europe in the first decade of the 20th century.
Natural, organic forms, especially flowers, were depicted by artists and designers in twisted, curved, entwined and elongated forms, and decorated with coloured glass, ceramic mosaics, or gold leaf paint, creating an overall effect of lush sensuality - which can at times be overwhelmingly cloying. Influenced by the symbolist poets, especially Baudelaire's Les Fleurs du Mal and the eroticism of Japanese shunga art, Art Nouveau also reflected a fascination with the nude female form as an object of male desire (to be deflowered), presented in highly decorative styles, and loaded with mythological and symbolic significance. The two motifs coalesced in the image of the flower woman, such as Louis Chalon's bronze figure, L'orchidee, in which a flower is depicted as a nude female figure.
Overexposure to this heady fusion of the exotic, the erotic, the symbolic and the florid can make the viewer run from the land of the lotus eaters, in search of a bracing dose of Modernist rigour. Not surprisingly there was a strong reaction against Art Nouveau in the decades after the first World War; its critical reputation dipped and it was dismissed as a noxious weed - fin-desiecle decadence at its most extreme. It flowered again in the 1960s and 1970s - remember all those Mucha posters? - when it found its natural successor in the psychedelia of those decades. It retains its appeal among adolescents, who respond to its excess.
The current exhibition at London's Victoria and Albert Museum, which runs until July 30th, is the largest of its kind to be held since the demise of the style itself. It is accompanied by a number of comprehensive, impeccably researched and beautifully illustrated V&A publications.
The show concentrates on objects rather than buildings; to see Art Nouveau architecture at its most developed and in its most concentrated setting, a neck-craning stroll through the streets of Barcelona is required. It's not called Art Nouveau there: confusingly, the Catalan variant of the style is called modernisme, although it has nothing to do with what the English-speaking world calls Modernism. The difference is more than linguistic: Catalan modernisme is a crystallisation of elements specific to the historical and cultural conditions of Catalunya at the turn of the 19th century. It reflected the aspirations of Catalan nationalism, which in those decades was undergoing a Renaixenca (Renaissance) in language, literature, music, especially choral singing, history, archaeology and mythology, similar to the nationalist revivals in many other European countries at the time. In 1901 the Catalan Nationalist party won the city council elections and set about extending the powers of city government, establishing Catalan institutions, which were designed in the Modernista style. A programme of modernisation and social reform was introduced, capitalising on the economic success of Catalunya, Spain's only industrial centre at the time. Using the readily available materials of iron, glass and reinforced concrete, the new architecture was a fusion of different styles, looking to Northern Europe, while also drawing on the traditions of Catalan Romanesque and Baroque and featuring national mythological symbols such as St George and the dragon. Many of the leading architects and craftsmen who emerged from the movement were also politicians, including Domenech I Montaner and Puig I Cadafalch, who designed private residences for the city's wealthy industrialists as well as public buildings that reflected their social conscience, such as psychiatric hospitals. Domenech's lavish Palau de la Musica Catalana, the national concert hall, was built to house the all-male Catalan choir, the Orfeo Catala. Using stained glass and mosaics throughout, and adorned with floral and Islamic motifs, it features a vast inverted glass cupola in the auditorium. The decoration is so lavish that even before any music is performed, the audience reels from the sensual assault.
Since the city hosted the Olympics in 1990 and was designated European Cultural Capital, Barcelona has restored and rediscovered its Modernista heritage with a vengeance. The visitor is now showered with detailed maps, videos and illustrated guides to The Modernisme Trail, which is packaged, gift-wrapped and labelled according to the criteria of cultural tourism, denying the visitor the excitement and pleasure of independent discovery and diluting the context of the buildings.
Antoni Gaudi is central to the Trail, of course. Once reviled, and now on the brink of canonisation, Barcelona's most famous architect possessed a singular visual imagination that emerges from the bedrock of modernisme but goes far beyond it, pushing it to sculptural extremes that anticipate the surrealism of Miro and Dali. A devout Catholic with an interest in mysticism and the occult, Gaudi reacted against the secularism of the Modernista movement and looked to Northern European Gothic, to Wagnerian symbolism, and Islamic design for his sources. Sinuous forms, drawn from the natural world are incorporated into his houses (Palau Guell, La Pedrera, Casa Batllo) and his churches (Colonia Guell and La Sagrada Familia, both unfinished). His elastic, undulating structures and expressionist decoration, using the trencadis technique (surfaces covered with irregular shaped pieces of glazed ceramic in a collage) are unmistakably individual.
He developed his own modelling technique with string and suspended weights, pursuing spatial freedom in ways that anticipated late-20th-century computer-aided architecture. In this he was matched by his associate, Josep Jujol, who designed the serpentine benches at Gaudi's Parc Guell which overlooks Barcelona. Jujol's own buildings in St Joan Despi: Can Negre and Torre de La Creu, with its five, mosaic domed cylinders and sharply defined edges, anticipate contemporary architects such as Juan Mirales and Frank Gehry.
Gaudi's Crypt for the church at Colonia Guell - a purpose-built workers' estate adjoining cotton mills on the outskirts of Barcelona - is a womblike sanctuary that seems ancient and elemental, evoking cave dwellings, but is full of innovation. It uses Gaudi's original form of arch, the hyperbolic parabola, which prises the sides of the traditional gothic arch apart like compass legs and creates an organic, sculptural space. It's a long way from Les Fleurs du Mal.
Art Nouveau 1890-1914 can be seen at the Victoria and Albert Museum until July 30th and will travel to Washington later this year. Further information on Catalan Modernisme, and Barcelona in general, from Turisme de Catalunya, London. Tel: 00 44 (0)20 7583 8855.