Movie musical Chicago has taken six Oscars at the 75th Academy Awards, becoming the first musical to win best film since Oliver! in 1968.
Chicago was the biggest winner on the night
Roman Polanski was the surprise winner of the best director award for The Pianist, while his lead actor Adrien Brody, 29, became the youngest ever winner of the best actor award.
Nicole Kidman took the best actress Oscar for her performance as Virginia Woolf in Stephen Daldry's The Hours.
A heavily pregnant Catherine Zeta Jones won best supporting actress.
"Oh my God - it's a a Scotsman giving a Welsh girl an Oscar," she said as she collected her prize from former James Bond star Sean Connery.
The Oscars had been toned down due to the Iraq conflict, with scaled-down red carpet entrances amid the ceremony's tightest security.
Kidman and Brody both cried during their speeches
Thousands of anti-war protesters gathered outside the Kodak Theatre in Hollywood, along with several hundred pro-war demonstrators, using the global event as a platform for their views.
Several big-name winners including Michael Moore, Pedro Almodovar and Chris Cooper also made their feelings about war known in their speeches.
The strongest comments during the ceremony came from Moore, whose film exploring US gun culture won the best documentary Oscar.
Moore, who invited his fellow nominees on stage with him, was booed as he said: "We live in the time where we have fictitious election results that elect a fictitious president."
"We live in a time where we have a man who's sending us to war for fictitious reasons."
MAIN OSCAR WINNERS
Chicago - 6
The Pianist - 3
Frida - 2
The Hours - 2
Lord of the Rings - 2
Adaptation - 1
Polanski's win caused a stir even though he was not at the ceremony.
He beat favourite Martin Scorsese, but has not set foot in the US since 1977 as he still faces charges for having sex with a 13-year-old girl.
Kidman and Brody both made reference to their sadness at war in Iraq in their acceptance speeches.
Kidman cried and said: "There are a lot of problems in the world since 9/11 and there's been a lot of pain and with the war families losing people - and God bless them."
Brody received a standing ovation when he said: "Whatever you believe in whether it's God or Allah may he watch over you and we pray for a swift resolution."
Zeta Jones is two weeks away from giving birth
First-time winner Brody, who played a Polish pianist who survived the Holocaust, beat four previous Oscar winners.
Spanish director Pedro Almodovar, who won best original screenplay for Talk To Her, added that his Oscar was for those "raising their voices in respect of peace democracy and international legality - all of which are essential qualities to live".
And actor Chris Cooper also made reference to the conflict with a plea for world peace as he won best supporting actor for his role in the film Adaptation.
Peter O'Toole, who won a lifetime achievement Oscar, joked as he said: "Always a bridesmaid never a bride, my foot - I now have my own Oscar now until death do us part."
Adrien Brody gave Halle Berry a huge kiss on stage
Rapper Eminem, who is also known for hitting headlines, won an Oscar for best original song for the film 8 Mile, but was not at the ceremony to collect his prize.
Best foreign film was won by Germany's Nowhere in Africa, a film directed by Caroline Link about the challenges faced by a German Jewish family who flee from the Nazis to Kenya.
And hit Japanese cartoon Spirited Away won the Oscar for best animated feature.
The awards began with host comic Steve Martin joking about the glamour at this year's event, and making jokes at the expense of several stars at the ceremony, including Jack Nicholson and Nicole Kidman.
"I'm glad they cut back on all the glitz - you probably noticed there was no fancy red carpet tonight. That'll send them a message," he said, referring to anti- and pro-war protests outside the ceremony.
The ceremony was being broadcast live in the US on TV network ABC, but it also broke off from the event to relay the latest news on the war in Iraq.