June 27, 1918

In the Paris of the early eighteen-nineties, at the height of the Decadence, the man of the moment was the novelist, art critic, and would-be guru Joséphin Péladan, who named himself Le Sâr, after the ancient Akkadian word for “king.” He went about in a flowing white cloak, an azure jacket, a lace ruff, and an Astrakhan hat, which, in conjunction with his bushy head of hair and double-pointed beard, gave him the aspect of a Middle Eastern potentate. He was in the midst of writing a twenty-one-volume cycle of novels, titled “La Décadence Latine,” which follows the fantastical adventures of various enchanters, adepts, femmes fatales, androgynes, and other enemies of the ordinary. His bibliography also includes literary tracts, explications of Wagnerian mythology, and a self-help tome called “How One Becomes a Magus.” He let it be known that he had completed the syllabus. He informed Félix Faure, the President of the Republic, that he had the gift of “seeing and hearing at the greatest distances, useful in controlling enemy councils and suppressing espionage.” He began one lecture by saying, “People of Nîmes, I have only to pronounce a certain formula for the earth to open and swallow you all.” In 1890, he established the Order of the Catholic Rose + Croix of the Temple and the Grail, one of a number of end-of-century sects that purported to revive lost arts of magic. The peak of his fame arrived in 1892, when he launched an annual art exhibition called the Salon de la Rose + Croix, which embraced the Symbolist movement, with an emphasis on its more eldritch guises. Thousands of visitors passed through, uncertain whether they were witnessing a colossal breakthrough or a monumental joke.

This is the beginning of a New Yorker article purporting to explicate "the occult roots of modernism." The focus is Josephin Péladan (March 28, 1858 to June 27, 1918.) His play “Oedipus and the Sphinx” (1903), like his novels, is not available in English.

The thesis of the New Yorker article is that "mystics like Péladan prepared the ground for the modernist revolution of the early twentieth century."

However
"In the wake of two catastrophic world wars, mysticism lost its lustre."

And people forgot about Péladan.

The historical situation is misrepresented in this article we link to.

Peladan was not an influential part of the story, merely the product of forces difficult to discern beneath the public clamor. His career was a late efflorescence of the shock consequent to the advances of the natural sciences. The term "mysticism" has lost any denotative value in this context, and Pelandan helped ground into rubble such useful stepping stones. His garish ideas about psychic powers, for instance, make it harder to recover authentic possibilities. 

His type however is still around and flourishing.