"The King's Speech," which stars Colin Firth, won the Academy Award for Best Picture on Sunday.
The film, by director Tom Hooper and producers Iain Canning, Emile Sherman and Gareth Unwin, beat "The Fighter," "Inception," "The Kids Are All Right," "Black Swan," "127 Hours," "The Social Network," "Toy Story 3," "True Grit" and "Winter's Bone."
"The King's Speech" won a total of four Oscars. In the movie, Firth portrays a stuttering UK monarch King George VI. Helena Bonham Carter plays his wife, Queen Elizabeth, and Geoffrey Rush portrays the king's speech therapist.
The movie was nominated for 12 Oscars, including ones for Firth, Bonham Carter and Rush.
Earlier, Colin Firth won the Academy Award for Best Actor in a Leading Role, "The King's Speech" screenwriter David Seilder won the Academy Award for Best Writing (Original Screenplay) and Tom Hooper won for Best Directing.
Last year, Firth was nominated for an Oscar for his role in the drama movie "A Single Man." He played a professor who struggles to cope with the sudden death of his partner.
Firth has also starred in films such as "Love, Actually," "Bridget Jones: The Edge of Reason," "The English Patient" and "Mamma Mia!."
Jane Fraser, president of The Stuttering Foundation, congratulated the cast of "The King's Speech," saying in a statement: "Tom Hooper gave us an inspirational hero, David Seidler gave us an impassioned voice, Helena Bonham Carter gave us a forceful yet supportive spouse, and Colin Firth and Geoffrey Rush portrayed the perfect relationship between therapist and patient, an alliance built upon unbreakable trust, mutual respect and lifelong friendship."
"The real winners tonight, however, are people who stutter, especially those who require the courage of a King to cope with stuttering on a daily basis," she added.