It originated in France and developed in Europe in the eighties of the nineteenth century and the first decade of the twentieth century. Find a consideration in the current artistic and architectural taken different names depending on the country in which flourished: Italian Art Nouveau, Art Nouveau in France, Jugendstil in Germany. The Decadent represents a significant response to the ideological aspects, moral and literary positivism. It was the exasperation of one of the two trends of Romanticism, one turned to the contemplation of a world of mystery and dream, expressing an extreme subjectivism, while realism and realism he had developed a tendency oggettiva.Il term "decadent "he was originally a negative sense; He was in fact directed against some poets who expressed bewilderment of conscience and the crisis of values of the late nineteenth century, devastated by the industrial revolution, by class conflicts, a progressive unleashing of imperialism, the decline of the noblest romantic ideals.These poets warned the failure of the most ambitious dream of Positivism: the conviction that science, destroying the "superstitions" religious, would be able to give a rational explanation of the mystery of life and comprehensive and would lay the foundations of a better coexistence of men. The Decadent was, above all, a mood of perplexity lost, a feeling of existential crisis, which came gradually deepening in the first half of this century, troubled by tragic experiences of wars, dictatorships, revolutions, and also from sconvolgenti.Due scientific discoveries are the fundamental aspects of decadent spirituality: the feeling of reality as a mystery and the discovery of a new dimension in the human spirit, that is, the unconscious, instinct, conceived as front and substantially higher than rationality. The new spirituality is linked to two main reasons of Romanticism: the obsessive sense of mystery and irrationalism.