Poiret dominated the world of couture between 1907 and the First World War as no personality had done since Worth, but by 1914 there were ominous signs that his work was not universally appreciated in France. In a controversy that revealed the extent to which the couture could be viewed as a serious and influential art, critics on the extreme right used criticism of Poiret's work to attack the whole panoply of early modernism as it had been developing in Paris.(29) In a climate rife with war-driven anti-German feeling, newspapers published diatribes against cubism, the Ballets Russes, contemporary music, and other manifestations of the avant-garde, which were called "Germanic" and "barbarian," a repudiation of all that was "French." Cartoons appeared in the press ridiculing Poiret's fashions for precisely the Orientalist details that had made them so popular. The "lampshade tunic" that Madame Poiret had worn at the "Thousand and Second Night" fête in 1911 was particularly recognizable and thus a symbol of all Poiret's work [see fig. 100, p. 138]. His well publicized sorties into Austria, Germany, and Eastern Europe to show his collections also made him an easy target. Beginning in 1915, the journal La Renaissance attacked Poiret for "boche taste." The fact that his creations were favorites in Germany was used to "prove" his sympathy for the enemy, the same argument used to place cubist art in the realm of "foreign snobs and indigenous neurotics," i.e., the avant-garde.(30) After several reiterations of this calumny, Poiret sued, which only served to perpetuate the scandal and remind people further of his connections with Germany. In the end, La Renaissance apologized publicly to Poiret, whose "subversive" work merely reflected the internationalist, cosmopolitan character of all modern art before World War I. Artists banded together to defend Poiret, but the damage was done.

After the War, Poiret fought to reestablish his reputation in France, aided by letters from the artists who knew and supported him. Dunoyer de Segonzac wrote an especially telling missive in which he praised Poiret as "a child of Paris," possessing "all the independence of spirit, fantasy, and candor" that implied. "In many ways, ‘Revolutionary' France has become more conservative than ‘Medieval' Germany," he concluded, recognizing that the slander of Poiret was not only an attack on fashion, but an offensive against all the arts.(31) In his perceptive book Esprit de Corps, Kenneth E. Silver has shown how these threats eventually intimidated French artists with their calls for a "return to order" and chilled the character of artworks produced after the War. Poiret approached the struggle to restore his name with his usual élan. Returning from the Front, he continued to produce his Orientalist fashions, and, during the Exposition of 1925, rented huge barges to show his works on the banks of the Seine, a grandiose gesture funded entirely by himself. Its outrageous cost, combined with the negative publicity generated by his critics, doomed his efforts to continue business in his pre-War style. Although some of his most beautiful creations date from this period and his popularity was at its height in the United States, he was forced to close his couture house entirely in 1929 [figs. 105-106].

The First World War brought many changes to the couture. Men like Paul Poiret and the young Jean Patou were drafted into the military, and their houses closed. Commerce was curtailed between France and the United States, and, although the Lyon silk industry remained in operation, many of its weavers, as well as its clients, were called into the army. Meanwhile, new personalities appeared, including the young Gabrielle Chanel. In 1915, Chanel was in Deauville producing hats and making her first essay into the couture with loose-fitting chemise dresses belted at the hip. By 1916, she was making casual pleated skirts from the practical Rodier wool jersey that had been used primarily for men's underwear before the war. She topped the skirts with Breton sailors' sweaters in the "sportswear" mode that had begun to appear in Vogue and the Gazette du Bon Ton several years earlier and that was to become so important in the 1920s. Chanel was still little known in the United States.

The French government regarded support of the couture industry to be essential during the War. It sent to the Panama Pacific International Exposition of 1915 in San Francisco a selection of apparel by the "old masters": Paquin, Doucet, Lanvin, Chéruit, Callot Soeurs, Doeuillet, de Beer, Premet, and Martial et Armand. Most had long full skirts with tucked-in waists, while tailored suits had long jackets with loose belts [fig. 107]. One or two designs even returned to corseting. All of these houses dated from early in the century. A mere handful of references to them appear in the Tirocchi record books of the 1920s. Only Lanvin, well represented by several models in the San Francisco exposition, was still a force among the Tirocchi clientele by the mid-1920s.