The film won a total of four Oscars including best picture and best director.
Eddie Redmayne and Julianne Moore were among the other big winners of the night.
See all of the Oscar winners below.
Winners are highlighted in bold.
Best Picture
"American Sniper"
"Birdman"
"Boyhood"
"The Grand Budapest Hotel"
"The Imitation Game"
"Selma"
"The Theory of Everything"
"Whiplash"
Best Actor
Steve Carell in "Foxcatcher"
Bradley Cooper in "American Sniper"
Benedict Cumberbatch in "The Imitation Game"
Michael Keaton in "Birdman or (The Unexpected Virtue of Ignorance)"
Eddie Redmayne in "The Theory of Everything"
Best Actress
Marion Cotillard in "Two Days, One Night"
Felicity Jones in "The Theory of Everything"
Julianne Moore in "Still Alice"
Rosamund Pike in "Gone Girl"
Reese Witherspoon in "Wild"
Best Supporting Actress
Patricia Arquette in "Boyhood"
Laura Dern in "Wild"
Keira Knightley in "The Imitation Game"
Emma Stone in "Birdman"
Meryl Streep in "Into the Woods"
Best Supporting Actor
Robert Duvall in "The Judge"
Ethan Hawke in "Boyhood"
Edward Norton in "Birdman or (The Unexpected Virtue of Ignorance)"
Mark Ruffalo in "Foxcatcher"
J.K. Simmons in "Whiplash"
Best Director
Alejandro G. Iñárritu "Birdman or (The Unexpected Virtue of Ignorance)"
Richard Linklater "Boyhood"
Bennett Miller "Foxcatcher"
Wes Anderson "The Grand Budapest Hotel"
Morten Tyldum "The Imitation Game"
Best Animated Feature Film
"Big Hero 6" Don Hall, Chris Williams, and Roy Conli
"The Boxtrolls" Anthony Stacchi, Graham Annable, and Travis Knight
"How to Train Your Dragon 2" Dean DeBlois, and Bonnie Arnold
"Song of the Sea" Tomm Moore and Paul Young
"The Tale of the Princess Kaguya" Isao Takahata and Yoshiaki Nishimura
Best Documentary Feature
"CitizenFour" Laura Poitras, Mathilde Bonnefoy, and Dirk Wilutzky
"Finding Vivian Maier" John Maloof and Charlie Siskel
"Last Days in Vietnam" Rory Kennedy and Keven McAlester
"The Salt of the Earth" Wim Wenders, Juliano Ribeiro Salgado, and David Rosier
"Virunga" Orlando von Einsiedel and Joanna Natasegara
Best Original Song
"Everything Is Awesome" from "The Lego Movie"
Music and Lyric by Shawn Patterson
"Glory" from "Selma"
Music and Lyric by John Stephens and Lonnie Lynn
"Grateful" from "Beyond the Lights"
Music and Lyric by Diane Warren
"I'm Not Gonna Miss You" from "Glen Campbell…I'll Be Me"
Music and Lyric by Glen Campbell and Julian Raymond
"Lost Stars" from "Begin Again"
Music and Lyric by Gregg Alexander and Danielle Brisebois
Achievement in music written for motion pictures (Original score)
"The Grand Budapest Hotel" Alexandre Desplat
"The Imitation Game" Alexandre Desplat
"Interstellar" Hans Zimmer
"Mr. Turner" Gary Yershon
"The Theory of Everything" Jóhann Jóhannsson
Achievement in cinematography
"Birdman or (The Unexpected Virtue of Ignorance)" Emmanuel Lubezki
"The Grand Budapest Hotel" Robert Yeoman
"Ida" Lukasz Zal and Ryszard Lenczewski
"Mr. Turner" Dick Pope
"Unbroken" Roger Deakins
Achievement in costume design
"The Grand Budapest Hotel" Milena Canonero
"Inherent Vice" Mark Bridges
"Into the Woods" Colleen Atwood
"Maleficent" Anna B. Sheppard and Jane Clive
"Mr. Turner" Jacqueline Durran
Best documentary short subject
"Crisis Hotline: Veterans Press 1" Ellen Goosenberg Kent and Dana Perry
"Joanna" Aneta Kopacz
"Our Curse" Tomasz Sliwinski and Maciej Slesicki
"The Reaper (La Parka)" Gabriel Serra Arguello
"White Earth" J. Christian Jensen
Achievement in film editing
"American Sniper" Joel Cox and Gary D. Roach
"Boyhood" Sandra Adair
"The Grand Budapest Hotel" Barney Pilling
"The Imitation Game" William Goldenberg
"Whiplash" Tom Cross
Best foreign-language film of the year
"Ida" Poland
"Leviathan" Russia
"Tangerines" Estonia
"Timbuktu" Mauritania
"Wild Tales" Argentina
Achievement in makeup and hairstyling
"Foxcatcher" Bill Corso and Dennis Liddiard
"The Grand Budapest Hotel" Frances Hannon and Mark Coulier
"Guardians of the Galaxy" Elizabeth Yianni-Georgiou and David White
Achievement in production design
"The Grand Budapest Hotel" Production Design: Adam Stockhausen; Set Decoration: Anna Pinnock
"The Imitation Game" Production Design: Maria Djurkovic; Set Decoration: Tatiana Macdonald
"Interstellar" Production Design: Nathan Crowley; Set Decoration: Gary Fettis
"Into the Woods" Production Design: Dennis Gassner; Set Decoration: Anna Pinnock
"Mr. Turner" Production Design: Suzie Davies; Set Decoration: Charlotte Watts
Best animated short film
"The Bigger Picture" Daisy Jacobs and Christopher Hees
"The Dam Keeper" Robert Kondo and Dice Tsutsumi
"Feast" Patrick Osborne and Kristina Reed
"Me and My Moulton" Torill Kove
"A Single Life" Joris Oprins
Best live-action short film
"Aya" Oded Binnun and Mihal Brezis
"Boogaloo and Graham" Michael Lennox and Ronan Blaney
"Butter Lamp (La Lampe Au Beurre De Yak)" Hu Wei and Julien Féret
"Parvaneh" Talkhon Hamzavi and Stefan Eichenberger
"The Phone Call" Mat Kirkby and James Lucas
Achievement in sound editing
"American Sniper" Alan Robert Murray and Bub Asman
"Birdman or (The Unexpected Virtue of Ignorance)" Martín Hernández and Aaron Glascock
"The Hobbit: The Battle of the Five Armies" Brent Burge and Jason Canovas
"Interstellar" Richard King
"Unbroken" Becky Sullivan and Andrew DeCristofaro
Achievement in sound mixing
"American Sniper" John Reitz, Gregg Rudloff and Walt Martin
"Birdman or (The Unexpected Virtue of Ignorance)" Jon Taylor, Frank A. Montaño, and Thomas Varga
"Interstellar" Gary A. Rizzo, Gregg Landaker, and Mark Weingarten
"Unbroken" Jon Taylor, Frank A. Montaño, and David Lee
"Whiplash" Craig Mann, Ben Wilkins, and Thomas Curley
Achievement in visual effects
"Captain America: The Winter Soldier" Dan DeLeeuw, Russell Earl, Bryan Grill and Dan Sudick
"Dawn of the Planet of the Apes" Joe Letteri, Dan Lemmon, Daniel Barrett and Erik Winquist
"Guardians of the Galaxy" Stephane Ceretti, Nicolas Aithadi, Jonathan Fawkner and Paul Corbould
"Interstellar" Paul Franklin, Andrew Lockley, Ian Hunter and Scott Fisher
"X-Men: Days of Future Past" Richard Stammers, Lou Pecora, Tim Crosbie and Cameron Waldbauer
Adapted screenplay
"American Sniper" Written by Jason Hall
"The Imitation Game" Written by Graham Moore
"Inherent Vice" Written for the screen by Paul Thomas Anderson
"The Theory of Everything" Screenplay by Anthony McCarten
"Whiplash" Written by Damien Chazelle
Original screenplay
"Birdman or (The Unexpected Virtue of Ignorance)" Written by Alejandro G. Iñárritu, Nicolás Giacobone, Alexander Dinelaris, Jr. & Armando Bo
"Boyhood" Written by Richard Linklater
"Foxcatcher" Written by E. Max Frye and Dan Futterman
"The Grand Budapest Hotel" Screenplay by Wes Anderson; Story by Wes Anderson & Hugo Guinness
"Nightcrawler" Written by Dan Gilroy