According to ew.com, Carter is the first African-American woman to take home an Oscar in this category. She was competing with Mary Zophres for "The Ballad of Buster Scruggs", Sandy Powell for "The Favourite" and "Mary Poppins Returns" and Alexandra Byrne for "Mary Queen of Scots".
Carter, a previous Oscar nominee for "Amistad" and "Malcom X", worked on the costumes for the entire fictional nation of Wakanda in Ryan Coogler's "Black Panther", crafting everything from Chadwick Boseman's superhero suit to the Dora Milaje's colourful armour. The award is also the first Oscar won by Marvel Studios.
"Marvel may have created the first black superhero, but through costume design, we turned him into an African king," Carter said in her acceptance speech.
"It's been my life's honour to create costumes. Thank you to the Academy, and thank you for honouring African royalty and the empowered way women can look and lead on screen."
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Carter also thanked Spike Lee, also a nominee this year for "BlacKkKlansman", for giving her her "start" with "Malcolm X".
"I hope this makes you proud," she added.
The award was presented by Melissa McCarthy and Brian Tyree Henry. McCarthy was seen wearing a gigantic train covered in toy rabbit and holding a toy rabbit.
There was another win for "Black Panther" as Hannah Beachler and Jay Hart took the golden statuette for Best Production Design. Beachler became the first African-American to be nominated and to win an Oscar in production design.
Beachler gave a moving speech in which she thanked the cast and crew of "Black Panther".
aI stand here with agency and self-worth because of (director) Ryan Coogler, who not only made me a better designer, a better storyteller, a better person," she said adding that he offered her patience and "better perspective of life".
She also shared the same advice she once received: "When you think things are impossible, remember I did my best, and my best is good enough."