The movie, which centres on a silent screen star (Jean Dujardin) who struggles with Hollywood's transition to talkies, triumphed over rivals Hugo, The Descendants, War Horse, The Help, Midnight in Paris, Moneyball, The Tree of Life and Extremely Loud & Incredibly Close.
The Artist is the first silent film to win 'Best Picture' since Wings in 1928. The coveted 'Best Picture' gong is one of five Oscars for The Artist, which also scooped 'Best Actor' for Dujardin, 'Director' for Hazanavicius, 'Costume Design' and 'Original Score'.
Hazanavicius said: "I'd like to say a very, very important thing. I want to say 'Hi' to my kids - and it's 6 o'clock in the morning in Paris, so you should go to bed in 30 seconds! I want to say to my wife, Berenice Bejo, that I love you, but it's not just about that... you inspired the movie, and you're the soul of the movie and the positive feeling of the movie."
He added: "I want to thank three people. I want to thank Billy Wilder, Billy Wilder and Billy Wilder. Thank you so much."
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Watch the trailer for The Artist below: