On an evening politically charged from the outset because of the #OscarsSoWhite controversy, those who accepted the coveted gold statues on stage used the occasion to highlight other issues and causes they believed in, ranging from the environment to lesbian, gay, bisexual and transgender (LGBT) rights to sexual abuse in the Catholic Church.
Speaking to the press backstage after his win at the Dolby Theatre in Los Angeles, Best Actor for The Revenant, Leonardo DiCaprio, 41, reiterated his earlier exhortation about climate change.
Even though he was still reeling from having won an Oscar finally after four previous acting nominations, he said: "It has been an amazing experience for me to stand there and not only talk about the film, but also something I've been obsessed with besides cinema, which is our environment and climate change.
"And I wanted to be able to speak about that on a platform with hundreds of millions of people watching, because to me, this is the most existential crisis our civilisation has ever known."
Added the star, who was flanked by The Revenant film-maker and Best Director winner Alejandro Gonzalez Inarritu, 52: "I'm so overwhelmed with gratitude tonight, but there is a ticking clock, we must all do something proactive about this issue.
"If you do not believe in climate change and modern science, you'll be on the wrong side of history. We need to vote for leaders who care about the future of this civilisation."
Tom McCarthy, 49, directed and co-wrote Best Picture winner Spotlight, which also won Best Original Screenplay. He hoped the film's retelling of the Boston Globe's 2001 expose on sexual abuse in the Catholic Church helps prevent further abuse.
Commenting on Snap - the Survivors Network of Those Abused by Priests - releasing a statement recently thanking the film-makers for highlighting the story, he said: "Our message is, 'We hear you. You are not alone. There's no shame in this. Come out. Speak loud. Be heard. And save lives.'
"And I think we all agree, inside and outside the Catholic Church, we got to do everything we can to protect the children."
Best Adapted Screenplay winners for The Big Short, Charles Randolph and Adam McKay, repeated their thank-you speech battle cry for Americans to stop voting for politicians taking money from "big banks, oil or weirdo billionaires".
McKay, 47, swears he was not singling out any one political party.
He said: "The amazing thing about this movie has been that we've seen conservative media host Bill O'Reilly and Democratic presidential candidate Bernie Sanders support this movie. Big money is taking over our government and until right and left go, 'No more big money', it has to be like a scarlet letter on these candidates.
"So I really, honestly, did not mean either side. Google it, you can see what the candidates have been paid. When you elect people who get money from banks and oil and weirdo billionaires, those are who they vote for."
British singer Sam Smith, 23, said it "meant the world" to him to talk about being a gay man on stage while accepting the Oscar for Best Original Song, which he won for the Spectre theme Writing's On The Wall.
"I was just bowled over and I wanted to take this opportunity to show how much I care about my community. In the past in my career, people have said that in the beginning I didn't, and I just wanted to make clear how much I care about the LGBT community."
Alicia Vikander, 27, won Best Supporting Actress for the romantic drama The Danish Girl, where she plays the wife of one of the first known recipients of gender reassignment surgery.
The Swedish star said she hoped the movie has helped people become more accepting of the transgender community.
She said: "I came on this film only two years ago and I know that this was not an easy film to get made, and to see the cultural change over the years since I finished the film, with Caitlyn Jenner coming out and with TV shows and films such as Transparent and Tangerine, it's like a social change.
"In the same way that this film has been so educational for me, I hope that it can open up an even wider conversation, if our film can be a part of that discussion."
But it was still a movie awards show at the end of the day, and the actors could not escape the inevitable horserace-type questions about winning.
The biggest upset of the night might have been Mark Rylance, the 56-year-old British performer whose win over sentimental favourite Sylvester Stallone - for Best Supporting Actor for Bridge Of Spies - drew gasps backstage.
Asked to comment on it, Rylance was modest, saying that although he knew some people felt "it's necessary to make a show out of it", he felt "I'm more like a spokesman when I win something" than someone who was better than his fellow nominees.
"So I don't take it too seriously," he said, adding that he has always enjoyed the work of supporting actors when he goes to the cinema.
Also not treating the Oscars as a race was The Revenant's Emmanuel "Chivo" Lubezski, 51, who took home his third consecutive win for Best Cinematography.
Asked midway through the ceremony if he was worried about all the technical wins Mad Max: Fury Road was chalking up at the expense of his movie, a revenge tale, the Mexican cinematographer said: "Honestly, I never saw the Academy Awards as a competition. I think it's something that you guys created.
"It's more a celebration of the craft and the art of film-making in general. And I'm just so lucky to be here. And I don't think it should be viewed as a competition because it's not objective. It's not, you know, five cinematographers running 100m to see who gets the Oscar first. It's very subjective and it's only 6,000 people who vote. So I'm just lucky. Doesn't mean I'm the best cinematographer."
Perhaps the biggest indirect winner yesterday was George Miller, director of Mad Max: Fury Road, whose six wins led to a long procession of winners coming through the interview room brandishing their wins for production and costume design, make-up and hairstyling, film editing, sound editing and sound mixing.
All of them thanked the 70-year- old Australian film-maker for his vision and creative generosity.
Sound editor Mark Mangini, 53, said: "He's one of the world's great collaborators. He's not a micromanager. He doesn't say, 'Do this. Do this. Do this.' He asks. He says, 'Here's what I'm trying to achieve with the film. How does sound complement that?' And then that gives us the room to be artists."
Repeat telecasts of the 88th Annual Academy Awards will air on HBO (StarHub TV Channel 601) on March 2 (9pm), March 4 (10.30pm) and March 6 (4pm).