Mucha moved to Paris in 1887, and continued his studies at Académie Julian and Academie Colarossi while also producing magazine and advertising illustrations.
Around Christmas 1894, Mucha happened to drop into a print shop where there was a sudden and unexpected demand for a new poster to advertise a play starring Sarah Bernhardt, the most famous actress in Paris, at the Theatre de la Renaissance. Mucha volunteered to produce a lithographed poster within two weeks, and on 1 January 1895, the advertisement for Gismonda appeared on the streets of the city.
It was an overnight sensation and announced the new artistic style and its creator to the citizens of Paris.Bernhardt was very satisfied with his work and commissioned further work.
Mucha produced a flurry of paintings, posters, advertisements, and book illustrations, as well as designs for jewellery, carpets, wallpaper, and theatre sets in what came to be known as the Art Nouveau style.
Mucha's works frequently featured beautiful healthy young women in flowing vaguely Neoclassical looking robes, often surrounded by lush flowers which sometimes formed haloes behind the women's heads. In contrast with contemporary poster makers he used paler colors.
The 1900 Universal Exhibition in Paris diffused the "Mucha style" internationally. He decorated the Bosnia-Herzegovina Pavilion and collaborated in the Austrian one.
His art nouveau style was often imitated. However, this was a style that Mucha attempted to distance himself from throughout his life; he insisted always that, rather than adhering to any fashionable stylistic form, his paintings came purely from within and Czech art. He declared that art existed only to communicate a spiritual message, and nothing more; hence his frustration at the fame he gained through commercial art, when he wanted always to concentrate on more lofty projects that would ennoble art and his birthplace. Source: Wikipedia
