Art Nouveau, a French term meaning new art, refers to a style of architecture, of commercial and decorative art, and, to some extent, a style of painting and sculpture that was popular about 1900. Although the style was then thought of as modern and was given the title "new art," it was adapted from older styles and art forms. Much was derived from the Gothic and Rococo and from the arts of Java and Japan. The movement was also inspired by Celtic manuscripts and the drawings of William Blake. Persian pottery and ancient Roman glass also served as models for some Art Nouveau craftsmen. The style's patterns and motifs were taken primarily from nature and were often carried out with unrestrained exuberance of form, color, and especially line. The characteristic line, a flowing curvilinear, was to give Art Nouveau the descriptive nicknames "noodle," "whiplash," "tapeworm," and "cigarette-smoke style."

A favorite Art Nouveau theme was a nymph with flowers in her abundant streaming hair. She appeared on the posters of Alfons Mucha and among the opals and moonstones of Rene Lalique's jewelry. Other favorites were peacocks, dragonflies, and moths. In brilliant enamels and gold filigree, they were worked into combs, brooches, and other adornments. Morning glories glimmered through the stained glass of Louis Comfort Tiffany. Irises were inlaid in the marquetry cabinets of Louis Majorelle (1859-1926). Cresting waves broke and seaweed clustered around Art Nouveau vases. A dish might be an unadorned lotus leaf. Other botanical forms were arranged in abstract patterns and were symmetrically arrayed around mirror or picture frames or repeated on fabrics and wallpapers or in mural decorations.

Art Nouveau was a rich, voluptuous style that appealed to an enlightened elite, to personalities such as Sarah Bernhardt and Loie Fuller, and to the nouveaux riches, whose tastes, uninhibited by tradition, encouraged designers to stylistic excesses. The style's patrons grew bored with it, however, and it declined in fashion within a decade. Yet not all Art Nouveau was frivolous and evanescent. Its serious adherents viewed it as the answer to a serious problem that had become apparent by the end of the 19th century: to find a style suitable for the industrial age rather than, as the academically trained architects of the Parisian École des Beaux-Arts were doing, applying past styles to contemporary works.