"The Artist" won five Academy Awards on Sunday including best picture, becoming the first silent film to triumph at Hollywood's highest honors since the original Oscar ceremony 83 years ago.
Among other prizes for the black-and-white comic melodrama were best actor for Jean Dujardin and director for Michel Hazanavicius.
The other top Oscars went to Meryl Streep as best actress for "The Iron Lady," Octavia Spencer as supporting actress for "The Help" and Christopher Plummer as supporting actor for "Beginners."
"The Artist" is the first silent winner since the World War I saga "Wings" was named outstanding picture at the first Oscars in 1929 had a silent film earned the top prize.
"I am the happiest director in the world," Havanavicius said, thanking the cast, crew and canine co-star Uggie. "I also want to thank the financier, the crazy person who put money in the movie."
The other wins for "The Artist" were musical score and art direction. Martin Scorsese's Paris adventure "Hugo" also won five Oscars, all in technical categories.
Streep's win was her first Oscar in 29 years, since she won best actress for "Sophie's Choice." She had lost 12 times in a row since then. Streep also has a supporting-actress Oscar for 1979's "Kramer vs. Kramer."
"When they called my name, I had this feeling I could hear half of America go, 'Oh, no, why her again?' But whatever," Streep said, laughing.
"I really understand I'll never be up here again. I really want to think all my colleagues, my friends. I look out here and I see my life before my eyes, my old friends, my new friends. Really, this is such a great honor but the think that counts the most with me is the friendship and the love and the sheer job we've shared making moves together," said Streep, the record-holder with 17 acting nominations.
Streep is only the fifth performer to receive three Oscars. Jack Nicholson, Ingrid Bergman and Walter Brennan all earned three, while Katharine Hepburn won four.
It was a night that went as expected, with front-runners claiming key prizes. Streep's triumph provided a bit of drama, since she had been in a two-woman race with Viola Davis for "The Help."
The biggest surprise may have been the length of the show, which clocked in at about three hours and 10 minutes, brisk for a ceremony that has run well over four hours some years.
The 82-year-old Plummer became the oldest acting winner ever for his role as an elderly widower who comes out as gay in "Beginners."
"You're only two years older than me, darling," Plummer said, addressing his Oscar statue in this 84th year of the awards. "Where have you been all my life? I have a confession to make. When I first emerged from my mother's womb, I was already rehearsing my Oscar speech."
The previous oldest winner was best-actress recipient Jessica Tandy for "Driving Miss Daisy," at age 80.
Completing an awards-season blitz that took her from Hollywood bit player to star, Spencer won for her role in "The Help" as a headstrong black maid whose willful ways continually land her in trouble with white employers in 1960s Mississippi.
Spencer wept throughout her breathless speech, in which she apologized between laughing and crying for running a bit long on her time limit.
"Thank you, academy, for putting me with the hottest guy in the room," Spencer said, referring to last year's supporting-actor winner Christian Bale, who presented her Oscar.
Dujardin became the first Frenchman to win an acting Oscar. French actresses have won before, including Marion Cotillard and Juliette Binoche.
"Oh, thank you. Oui. I love your country!" said Dujardin, who plays George Valentin, a silent-film superstar fallen on hard times as the sound era takes over. If George Valentin could speak, Dujardin said, "he'd say ... 'Merci beaucoup, formidable!'"
Claiming Hollywood's top-filmmaking honor completes Hazanavicius' sudden rise from popular movie-maker back home in France to internationally celebrated director.
Hazanavicius had come in as the favorite after winning at the Directors Guild of America Awards, whose recipient almost always goes on to claim the Oscar.
The win is even more impressive given the type of film Hazanavicius made, a black-and-white silent movie that was a throwback to the early decades of cinema. Other than Charles Chaplin, who continued to make silent films into the 1930s, and Mel Brooks, who scored a hit with the 1976 comedy "Silent Movie," few people have tried it since talking pictures took over in the late 1920s.
The only other filmmaker from France to win the directing Oscar is "The Pianist" creator Roman Polanski, who was born in France, moved to Poland as a child and has lived in France since fleeing Hollywood in the 1970s on charges he had sex with a 13-year-old girl.
Hazanavicius, known in his home country for the "OSS 117" spy comedies but virtually unheard of in Hollywood previously, won a prize that eluded half a dozen of France's most-esteemed filmmakers, including Jean Renoir, Francois Truffaut and Louis Malle, who all were nominated for directing Oscars but never won.
The five Oscars for "Hugo," which led contenders with 11 nominations, included cinematography, art direction and visual effects.
The visual-effects prize had been the last chance for the "Harry Potter" franchise to win an Oscar. The finale, "Harry Potter and the Deathly Hallows: Part 2," had been nominated for visual effects and two other Oscars but lost all three. Previous "Harry Potter" installments had lost on all nine of their nominations.
The teen wizard may never have struck Oscar gold, but he has a consolation prize: $7.7 billion at the box office worldwide, including $1.3 billion from "Deathly Hallows: Part 2," last year's top-grossing movie.
"And yet they only paid 14 percent income tax," Oscar host Billy Crystal joked about the "Potter" franchise.
Another beloved big-screen bunch, the Muppets, finally got their due at the Oscars. "The Muppets" earned the best-song award for "Man or Muppet," the sweet comic duet sung by Jason Segel and his Muppet brother in the film, the first big-screen adventure in 12 years for Kermit the frog and company.
Earlier Muppet flicks had been nominated for four music Oscars but lost each time, including the song prize for "The Rainbow Connection," Kermit's signature tune from 1979's "The Muppet Movie."
"I grew up in New Zealand watching the Muppets on TV. I never dreamed I'd get to work with them," said "Man or Muppet" writer Bret McKenzie of the musical comedy duo Flight of the Conchords," who joked about meeting Kermit for the first time. "Like many stars here tonight, he's a lot shorter in real life."
Filmmaker Alexander Payne picked up his second writing Oscar, sharing the adapted-screenplay prize for the Hawaiian family drama "The Descendants" with co-writers Nat Faxon and Jim Rash. Payne, who also directed "The Descendants," previously won the same award for "Sideways."
Payne said he brought along his mother from Omaha, Neb., to the Oscars, and that she had demanded a shout-out if he made it onstage.
"She made me promise that if I ever won another Oscar I had to dedicate it to her just like Javier Bardem did with his Oscar. So mom, this one's for you. Thank you for letting me skip nursery school so we could go to the movies."
Woody Allen earned his first Oscar in 25 years, winning for original screenplay for the romantic fantasy "Midnight in Paris," his biggest hit in decades. It's the fourth Oscar for Allen, who won for directing and screenplay on his 1977 best-picture winner "Annie Hall" and for screenplay on 1986's "Hannah and Her Sisters."
Allen also is the record-holder for writing nominations with 15, and his three writing Oscars ties the record shared by Charles Brackett, Paddy Chayefsky, Francis Ford Coppola and Billy Wilder.
No fan of awards shows, Allen predictably skipped Sunday's ceremony, where he also was up for best director and "Midnight in Paris" was competing in vain for best picture.
Best-picture front-runner "The Artist," which ran second to "Hugo" with 10 nominations, won Oscars for musical score and costume design.
"Rango," with Johnny Depp providing the voice of a desert lizard that becomes a hero to a parched Western town, won for best animated feature.
"Someone asked me if this film was for kids, and I don't know. But it was certainly created by a bunch of grown-ups acting like children," said "Rango" director Gore Verbinski, who made the first three of Depp's "Pirates of the Caribbean" movies.
Crystal got the show off to a lively start with a star-laden montage in which he hangs out with Justin Bieber and gets a nice wet kiss from George Clooney.
Back as Oscar host for the first time in eight years, Crystal also did his signature introduction of the best-picture nominees with a goofy song medley.
Spoofing a scene from "Midnight in Paris," Bieber told Crystal he was there to bring in the 18-to-24-year-old demographic for the 63-year-old host.
Crystal's return as host seemed appropriate on a night that had Hollywood looking back fondly on more than a century of cinema history.
The top two nominees — "Hugo" and "The Artist" — are both love songs to early cinema.
Add the Marilyn Monroe tale "My Week with Marilyn" — which earned Michelle Williams a best-actress nomination as the Hollywood's greatest sex goddess and Kenneth Branagh a supporting-actor nomination as Oscar winner Laurence Olivier — and the show's producers had a ready-made script for a night of fond recollection and backslapping about show business.
Associated Press Entertainment Writers Lynn Elber and Christy Lemire contributed to this report.