The 1940s occupation and postwar (1940-1947)
Lucien Lelong
The couturier who, as head of the Paris couture trade body, talked the German occupiers out of moving French fashion to Berlin - and whose house trained both Christian Dior and Pierre Balmain during the war.
Lucien Lelong is an odd sort of entry for a designers section, because his biggest contribution to the 1940s wasn't a silhouette or a garment - it was keeping Paris couture in Paris at all. He'd run a successful, elegant couture house since the 1920s, but from 1937 he was also president of the Chambre Syndicale de la Couture Parisienne, the trade body that governed the couture houses. That position put him squarely in charge when the Germans occupied Paris in 1940.
The occupiers had a plan to relocate the whole couture industry - houses, workrooms, skilled staff - to Berlin and Vienna. Lelong argued, over a long series of negotiations, that couture couldn't simply be picked up and moved: it depended on a whole ecosystem of Parisian embroiderers, button makers, feather workers, and specialist ateliers built up over generations. He won, and he also negotiated to keep some ninety houses open under exemptions from the harshest fabric rules. It's easy to read that as a straightforward heroic story, and there's real courage in it, but it's also genuinely complicated - those houses stayed open partly by dressing the wives of German officers and wealthy collaborators, which the occupation entry gets into more honestly.
The other reason Lelong matters is who worked for him. Both Christian Dior and Pierre Balmain spent the war as designers in his house, learning from each other and from Lelong's own refined, restrained sense of cut. When Balmain left to open his own house in 1945 and Dior followed in 1946, they took that training with them - so the postwar softening and, eventually, the New Look itself are in a real sense children of Lelong's wartime studio. He retired in 1948 without ever becoming a household name the way his protégés did, which I think is one of the decade's quieter injustices.