Campion began her acceptance speech in te reo Māori, addressing those watching from Aotearoa at home.
"Thank you Academy ... it's the honour of a lifetime," she said.
And in one of the most shocking moments in Oscars history, Will Smith took a swing at comedian Chris Rock for a joke he made about Jada Pinkett Smith while presenting the award for best documentary.
"Get my wife's name out of your f****** mouth," Smith shouted as he walked off stage.
His words were not bleeped out on TVNZ's live stream of the event.
When contacted for comment, a spokesperson for TVNZ said, "Given the live nature of the event, we're unable to predict what's about to happen and make cuts in advance."
Moments later, he returned to the stage to accept the award for Best Actor for his role as Richard Williams, the father of tennis greats Venus and Serena Williams, in King Richard.
In his speech he paid tribute to Williams as a "fierce defender of his family" and said he was called to "protect his family".
And Jessica Chastain has landed the award for Best Actress for her role in The Eyes of Tammy Faye.
It's the third nomination and the first win for the actress.
CODA's Troy Kotsur has taken home the Oscar for Best Supporting Actor, while Ariana DeBose won Best Supporting Actress for her role in West Side Story. Each made history on the night, with Kotsur the first deaf man to win an acting Oscar and DeBose the first openly queer woman of colour to do so.
Dune scooped up several awards including for its sound, visual effects, score, editing and production design.
Meanwhile, brother and sister duo Billie Eilish took home the Oscar for Best Original Song for No Time to Die in the latest James Bond film of the same name.
The pair thanked their collaborators and their parents for being their "biggest inspirations".
Follow our live blog for the latest from the Oscars stage.
Ahead of the ceremony today, Kiwi film producer Grant Major, nominated for his work on Campion's film, gave some insights into how the Oscars work.
Major won an Oscar for his work on The Lord of the Rings: The Return of the King, which scooped up the most Oscars ever awarded to a New Zealand-made film in 2004 with 11 wins.
Speaking to Newstalk ZB's Mike Hosking, Major said the Oscars "never get boring" and said it was an "exciting day".
While America is a little more relaxed than New Zealand in terms of Covid restrictions, he said there was still a lot of protocol to follow to get into the Oscars.
Major added that he knew from the start that Campion's film was "going to be special".
"From the word go when I first met Jane, I read the script, she showed me the script and I thought it was the best script I've ever read.
"I very much believe it's the best film - and the best director."
The full list of Oscar nominations and winners:
Best Picture:
Belfast
WINNER: CODA
Don't Look Up
Drive My Car
Dune
King Richard
Licorice Pizza
Nightmare Alley
The Power of the Dog
West Side Story
Best Director:
Paul Thomas Anderson (Licorice Pizza)
Kenneth Branagh (Belfast)
WINNER: Jane Campion (The Power of the Dog)
Steven Spielberg (West Side Story)
Ryusuke Hamaguchi (Drive My Car)
Best Actress:
WINNER: Jessica Chastain (The Eyes of Tammy Faye)
Olivia Colman (The Lost Daughter)
Penelope Cruz (Parallel Mothers)
Nicole Kidman (Being the Ricardos)
Kristen Stewart (Spencer)
Best Actor:
Javier Bardem (Being the Ricardos)
Benedict Cumberbatch (The Power of the Dog)
Andrew Garfield (Tick, Tick … Boom!)
WINNER: Will Smith (King Richard)
Denzel Washington (The Tragedy of Macbeth)
Best Supporting Actress:
Jessie Buckley (The Lost Daughter)
WINNER: Ariana DeBose (West Side Story)
Judi Dench (Belfast)
Kirsten Dunst (The Power of the Dog)
Aunjanue Ellis (King Richard)
Best Supporting Actor:
Ciaran Hinds (Belfast)
WINNER: Troy Kotsur (CODA)
Jesse Plemons (The Power of the Dog)
J.K. Simmons (Being the Ricardos)
Kodi Smit-McPhee (The Power of the Dog)
Best Costume Design:
WINNER: Cruella (Jenny Beavan)
Cyrano (Massimo Cantini Parrini)
Dune (Jacqueline West)
Nightmare Alley (Luis Sequeira)
West Side Story (Paul Tazewell)
Best Sound:
Belfast
WINNER: Dune
No Time to Die
The Power of the Dog
West Side Story
Best Original Score:
Don't Look Up (Nicholas Britell)
WINNER: Dune (Hans Zimmer)
Encanto (Germaine Franco)
Parallel Mothers (Alberto Iglesias)
The Power of the Dog (Jonny Greenwood)
Best Adapted Screenplay:
WINNER: CODA (Sian Heder)
Drive My Car (Ryusuke Hamaguchi and Takamasa Oe)
Dune (Eric Roth, Jon Spaihts and Denis Villeneuve)
The Lost Daughter (Maggie Gyllenhaal)
The Power of the Dog (Jane Campion)
Best Original Screenplay:
WINNER: Belfast (Kenneth Branagh)
Don't Look Up (Adam McKay and David Sirota)
Licorice Pizza (Paul Thomas Anderson)
King Richard (Zach Baylin)
The Worst Person in the World (Eskil Vogt, Joachim Trier)
Best Animated Short:
Affairs of the Art
Bestia
Boxballet
Robin Robin
WINNER: The Windshield Wiper
Best Live Action Short:
Ala Kachuu — Take and Run
The Dress
WINNER: The Long Goodbye
On My Mind
Please Hold
Best Film Editing:
Don't Look Up (Hank Corwin)
WINNER: Dune (Joe Walker)
King Richard (Pamela Martin)
The Power of the Dog (Peter Sciberras)
Tick, Tick… Boom! (Myron Kerstein and Andrew Weisblum)
Best Makeup and Hairstyling:
WINNER: The Eyes of Tammy Faye
House of Gucci
Coming 2 America
Cruella
Dune
Best Animated Feature:
WINNER: Encanto
Flee
Luca
The Mitchells vs. The Machines
Raya and the Last Dragon
Best Documentary Feature:
Ascension
Attica
Flee
WINNER: Summer of Soul
Writing With Fire
Best Documentary Short:
Audible
Lead Me Home
WINNER: The Queen of Basketball
Three Songs for Benazir
When We Were Bullies
Best Original Song:
Be Alive — Beyonce Knowles-Carter and Darius Scott (King Richard)
Dos Oruguitas — Lin-Manuel Miranda (Encanto)
Down to Joy — Van Morrison (Belfast)
WINNER: No Time to Die — Billie Eilish and Finneas O'Connell (No Time to Die)
Somehow You Do — Diane Warren (Four Good Days)
Best Cinematography:
WINNER: Dune (Greig Fraser)
Nightmare Alley (Dan Lausten)
The Power of the Dog (Ari Wegner)
The Tragedy of Macbeth (Bruno Delbonnel)
West Side Story (Janusz Kaminski)
Best International Feature:
WINNER: Drive My Car (Japan)
Flee (Denmark)
The Hand of God (Italy)
Lunana: A Yak in the Classroom (Bhutan)
The Worst Person in the World (Norway)
Best Production Design:
WINNER: Dune (Zsuzsanna Sipos and Patrice Vermette)
Nightmare Alley (Tamara Deverell and Shane Vieau)
The Power of the Dog (Grant Major and Amber Richards)
The Tragedy of Macbeth (Stefan Dechant and Nancy Haigh)
West Side Story (Rena DeAngelo and Adam Stockhausen)
Best Visual Effects:
WINNER: Dune
Free Guy
Shang-Chi and the Legend of the Ten Rings
No Time to Die
Spider-Man: No Way Home
