This difference is explained by the presence of a country's historical roots. Paris and France were always associated with delicacy, beauty, elegance, luxury and expensive materials. Rococo and Baroque fitted in the context of France almost naturally, the decorative aspect of the two styles is what the society (especially the noble part of it) needed and craved for. Although Art Nouveau is translated as the 'New Art', it combined and modified many past styles and mentality of the people. Like so the French Art Nouveau is different to other countries practicing the same style.
On the other hand there is the British Art Nouveau, where the past of Celts and Vikings strived. The English ancestors lived in a harsh and cold climate, living in those times was a struggle between life and death. The character of British people was tempered with rudeness, power, order and strict upbringing. The fighting for land and religion substantiated another context for Art Nouveau, which is more moderate, minimalist and less decorative. The Celtic past is a significant influence almost on a genetic level, since it is everywhere in Britain. The illuminated manuscripts, architectural ornamentation, jewellery and practically anything that was related to design was reflecting a Celtic manner of living, designing and decorating.
Despite the fact that the style of Art Nouveau varied internationally, the differences are not sufficient enough to call it a different style. The choice of materials, the medium, the stylistic qualities are the things that connect it to one same style. With industrialisation, the use of forged industrial metal, leaded glass, the popularity of posters and the new techniques for ceramic and glass work . The asymmetry of designs, the inspiration from plants, animals, and sensuous women. The most renowned styles of ancient Egypt, Japanese prints were also sources of inspiration that were creating a connection between Art Nouveau of different nations and countries.
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