Lupita Nyong'o cried herself to sleep after losing Kenyan accent for Hollywood roles: 'Full of heartbreak'

"I didn't feel like myself," the "Us" star said.

Oscar-winning actress Lupita Nyong'o has explained an unexpectedly painful part of her early life as an actress: losing the accent that she had acquired growing up in Kenya.

"The first permission I gave myself to change my accent or allow my accent to transform was going to drama school," the Yale School of Drama grad explained on a recent episode of What Now? with Trevor Noah podcast. "I went to drama school because I didn't want to just be an instinctive actor. I wanted to understand my instrument. I wanted to know what I was good at, what I was not good at, and work on the things that I wasn't good at. And one of the things I wasn't good at was accents."

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Nyong'o, who took home her Academy Award for her portrayal of the enslaved Patsey in 2013's 12 Years a Slave, was born in Mexico, but spent her childhood in the East African country.

"I didn't know how to sound any other way than myself," she said. "That was the first permission that I gave myself. But it was full of heartbreak and grief, just grief."

The pain came from feeling like someone else.

"The process of deciding, OK, I'm going to start working on my American accent and I'm not going to allow myself to sound Kenyan, so that I'm like monitoring and really trying to understand my mouth in a technical way to like make these new sounds. Making those new sounds in a context that wasn't the classroom felt like betrayal," she said. "You know, I didn't feel like myself and I cried many nights to sleep many, many nights."

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Following her breakthrough role, which was among her first handful of professional projects, Nyong'o has joined blockbuster franchises Star Wars, playing the 1,000-year-old former smuggler Maz Kanata via a performance-capture suit, and Black Panther, in which she costars as Nakia, the love interest of the late Chadwick Boseman. She also voices the main character in Wild Robot, which is now in theaters and on streaming.