The reality star, 41, stunned in Monroe's iconic gown worn to sing Happy Birthday to President John F. Kennedy almost 60 years ago.
Kardashian, who attended the gala with Pete Davidson, told Vogue the inspiration came to her last year after her infamous Balenciaga bodysuit. She said: "I thought to myself, what would I have done for the American theme if it had not been the Balenciaga look? What’s the most American thing you can think of? And that’s Marilyn Monroe."
Unfortunately, the fitting didn't go to plan when the dress was sent out to her Los Angeles home a few weeks ago.
"The dress was transported by guards and I had to wear gloves to try it on," Kardashian told the magazine. "I always thought she was extremely curvy. I imagined I might be smaller in some places where she was bigger and bigger in places where she was smaller. So when it didn't fit me I wanted to cry because it can't be altered at all."
The failed fitting prompted her to lose weight ahead of the hotly anticipated event. She cut out sugar and carbs, ran on the treadmill and wore a sauna suit twice a day.
"It was like a role, I was determined to fit it," she told La La Anthony during Vogue's Met Gala live stream.
"I didn't starve myself, but I was so strict," she said. "Just the cleanest veggies and protein."
Despite reaching her gala goal, the SKIMS founder only wore the original Monroe dress for a few minutes because of its fragility. She soon switched into a replica gown for the night. She also shared that it took her 14 hours to dye her hair bleach blonde for the evening.
After three weeks of intense dieting, Kardashian said she plans on celebrating with doughnuts and pizza.
Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.