High fashion has, historically, not been a welcoming place for plus-size customers, even if Ashley Graham has made it to the cover of Vogue a few times. Culturally, women with bodies well outside the range of sample sizes were not embraced — Karl Lagerfeld, the Chanel designer, often made his ungenerous feelings about larger women known — and there were almost no places to buy well-made or fancy clothes, even if you had the money and the desire for them.

Why invest in clothes if your body was considered undesirable, or when you were one successful diet away from the necessity of wearing them in the first place?

“Plus-size women have never been told they could stay that way and invest in themselves as they are,” said Lauren Chan, who started Henning last year. “Before this chapter, I was a plus-size model and a fashion news director at Glamour. I had these incredible colleagues wearing Miu Miu every day like they had that armor on, but my weight fluctuated, and I wore from size 12 to 20. I was in meeting in C-suites in Condé Nast wearing Forever 21.”

Henning blazers have a trim on the lining with a pep talk that reads: “Wear it like you mean it.”

“SINCE I WAS A PRETEEN, I was a size 14 and up,” said Aidy Bryant, the “Shrill” star, “Saturday Night Live” player and a founder, with the costume designer Remy Pearce, of the plus-size line Pauline. “I feel like so much of my youth was going to the mall or stores with my friends and watching them shop and being like, ‘I’ll buy a hair clip.’”