Lupita Nyong'o's whirlwind awards season (and emergence as a red carpet fashion fixture) ended Sunday with a best supporting actress Oscar for her role in "12 Years a Slave."

The 31-year-old actress, who made an indelible impression with her harrowing performance as a tortured slave, gave an emotional acceptance speech as she picked up the award for the breakout role in what was her feature film debut.

"Thank you to the Academy for this incredible recognition. It doesn't escape me for one moment that so much joy in my life is due to so much pain in someone else's," she said, referring to Patsey, the character she played in director Steve McQueen's wrenching 19th-century drama. "Thank you so much for putting me in this position," she told the director, tearfully. "It has been the joy of my life."

She credited McQueen for bringing attention to a dark chapter in American history and the victims of slavery. "I'm certain the dead are standing about you and watching," she said, a sentiment she expanded on backstage. "I think he's really honored a people that really have been unsung for a really long time in doing this film," she said. Nyong'o, who has talked about learning as a child to accept her dark-skinned beauty, said she hoped her success would inspire other youngsters.

"When I look down at this golden statue, may it remind me and every child, no matter where you're from, your dreams are valid," she said.