De Zayas's witty cartoons caught the attention of Stieglitz, who invited him to exhibit his work at 291. The first show, in 1909, went almost unnoticed, but the second one, the following year, was a huge success. The exhibition presented some 100 tridimensional cardboard caricatures of the most prominent New Yorkers of the time parading along 5th Avenue, with a sketch of the Plaza Hotel and Central park on the background.
In October 1910, de Zayas took a year-long trip to Paris to scout new talent for 291. It was in Paris that he discovered the bold new experiments taking place among Europe's avant-garde. He was one of the original happy few who got first hand exposure to Cubism and met Picasso. He also became acquainted with the poet and art collector Guillaume Apollinaire, who introduced him to African art, which had a deep influence on Cubism. Along with Walter Pach—one of the organizers of the Armory show—and a handful of other artists, de Zayas began to cement the link between the then-capital of the art world and New York, the emerging art power of the Western Hemisphere.
Part of that work included promoting Picasso, whose genius de Zayas had recognized immediately. "Pablo Picasso … finds himself in the first rank among innovators, a man who knows what he wants, and wants what he knows, who has broken with all school prejudices, has opened for himself a wide path, and has already acquired the notoriety which is the first step towards glory," de Zayas wrote in the first significant article on Picasso ever published in the United States (first in Spanish at América, then in English at Stieglitz's journal Camera Work). He also arranged the landmark Picasso show at 291.
De Zayas eventually opened his own gallery in New York, which he used to passionately promote the art he loved. In the early 1920s, de Zayas moved to Europe, where he would remain until the end of WWII. After the war he moved back to the United States. He and his wife made their home in Greenwich, Connecticut, where he died in 1961.
While de Zayas may not be as well-known as his collaborator Stieglitz, his contributions to the development of modernism in the United States are not entirely forgotten. The latest example is "African Art, New York and the Avant-Garde," a show running at the Metropolitan Museum of Art through April 14. One section is devoted to de Zayas's influence. "Describing himself as a 'propagandist for modern art,' de Zayas promoted little-known art forms in his New York gallery through innovative juxtapositions and thought-provoking exhibitions, impacting several of the most adventurous collections of the era," says Yaëlle Biro, the curator of the show.
What de Zayas didn't do was promote himself. "He never really made any effort to challenge the precedence of Stieglitz," wrote Naumann in an email.
His influence, however, is nonetheless still evident for those who know where to look for it.