South Korean black comedy "Parasite" made movie history at the Oscars on Sunday, becoming the first non-English-language film to win the best picture award -- Hollywood's biggest prize of all.
A genre-defying thriller about a poor family infiltrating a wealthy household, "Parasite" won four awards, stunning the pundits who believed the Academy would never crown a subtitled Asian movie.
"It's such a great honor. I feel like I'll wake up to find it's all a dream. It all feels very surreal," a jubilant Bong told journalists backstage, calling the night "crazy."
"Parasite" also won the Oscar for best international feature, and became the first Asian film to scoop best original screenplay.
"I thought I was done for the day and ready to relax," Bong had said upon winning best director honours, before promising to "drink until next morning."
Bong also paid tribute on stage to his childhood hero and fellow nominee Martin Scorsese, drawing a standing ovation for the veteran director of "The Irishman" -- which went home empty-handed.
But a bigger shock was in store as the movie beat frontrunner "1917" to win best picture, the night's final prize.
"It feels like a very opportune moment in history is happening right now," producer Kwak Sin-ae told an audience of Tinseltown A-listers, who cheered the film's wins throughout the night at the Dolby Theatre.
Bong predicted that "naturally we will come to a day" when "a foreign language film winning this won't be much of an issue."
The pre-Oscars favourite "1917," Sam Mendes's innovative and personal World War I movie about two soldiers crossing no-man's-land, had to settle for best cinematography, visual effects and sound mixing prizes.
The movie -- filmed to appear like one continuous shot -- had swept up trophies at several other galas in the build-up to Sunday.
Joaquin Phoenix won his first Oscar for his turn in supervillain origin story "Joker," the film that started the night with the most nominations.
In an emotionally charged speech, the actor railed against injustice and "an egocentric worldview" that leads to environmental destruction, before paying tribute to his actor brother River, who died of a drug overdose in 1993.
Renee Zellweger sealed a remarkable comeback by winning best actress for "Judy," dedicating the award to the Hollywood screen legend she portrayed.
"Judy Garland did not receive this honour in her time. I am certain that this moment is an extension of the celebration of her legacy," she said in accepting her second Oscar.
Pitt, who claimed his first acting Academy Award for his supporting turn in Quentin Tarantino's "Once Upon a Time... in Hollywood," was one of several winners to strike a political note.
"They told me I only have 45 seconds up here, which is 45 seconds more than the Senate gave John Bolton this week," he said, referring to President Donald Trump's recent impeachment trial.
"American Factory" -- the first film from Barack and Michelle Obama's production house, about a Rust Belt factory reopened by a Chinese billionaire -- won best documentary.
Best adapted screenplay went to Nazi satire "Jojo Rabbit," about a young boy corrupted by fascism.
Taika Waititi, who is of Maori origin, said he hoped the win would inspire "all the indigenous kids in the world who want to do art and dance and write stories."
Laura Dern won best supporting actress for her turn as a feisty divorce lawyer in "Marriage Story."
The event's luxury and glamour contrasted with the grief in Los Angeles over the recent deaths of Golden Age film legend Kirk Douglas and Oscar-winning basketball star Kobe Bryant.
Record Grammy-winning singer Billie Eilish sang a moving version of "Yesterday" to accompany the "in memoriam" montage for those Hollywood lost this year, which opened with Bryant and closed with Douglas.
Music was a prominent theme throughout the night, which began with a medley addressing a swirling row over the lack of minorities and female directors on the star-studded nominee list.
"We celebrate all the women who directed phenomenal films and I'm so proud to stand here as a black, queer artist," singer Janelle Monae said.
Elton John won for best original song from "Rocketman," a film about his life.
Rapper Eminem, who won an Oscar in 2003, made a surprise appearance on stage to perform his winning song "Lose Yourself" -- which was heavily bleeped out by censors.
Icelandic composer Hildur Gudnadottir won best original score for her haunting music for "Joker."
"To the girls, to the women, to the mothers, to the daughters, who hear the music bubbling within, please speak up," she said. "We need to hear your voices."
No female directors were nominated this year -- a theme referred to by several celebrities.
Natalie Portman, a best actress Oscar winner in 2011 for "Black Swan," literally wore her feelings -- she had their names stitched into the Dior cape she wore to the gala.
The ceremony had no host for a second consecutive time. Early reviews were not favorable.
"When the ads are the real stars, you really have a really serious problem," wrote Deadline Hollywood, calling the ceremony "way too long."