(CNN) Well, all that beard growing and bison liver-eating paid off.
Nineteen years after "Titanic" made him a global star, Leonardo DiCaprio finally won an Oscar Sunday night for his uncompromising role as a vengeful frontiersman in "The Revenant," his first win after coming away empty-handed at four previous Academy Awards shows.
The actor, 41, was composed but heartfelt in his best actor acceptance speech, in which he thanked mentor Martin Scorsese and urged viewers to combat climate change.
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"Making 'The Revenant' was about man's relationship to the natural world, a world that we collectively felt in 2015 as the hottest year in recorded history. Our production needed to move to the southern tip of this planet just to be able to find snow," he said.
"Climate change is real. It is happening right now. It is the most urgent threat facing our entire species, and we need to work collectively together and stop procrastinating. We need to support leaders around the world who do not speak for the big polluters or the big corporations, but who speak for all of humanity, for the indigenous people of the world, for the billions and billions of underprivileged people who will be most affected by this, for our children's children, and for those people out there whose voices have been drowned out by the politics of greed.
"I thank you all for this amazing award tonight. Let us not take this planet for granted. I do not take tonight for granted."
The actor received his first Oscar nomination in 1994 for his supporting role as Johnny Depp's mentally disabled little brother in "What's Eating Gilbert Grape." But the award went to Gene Hackman for "Unforgiven." DiCaprio was later nominated for playing Howard Hughes in 2005's "The Aviator," a diamond smuggler in 2006's "Blood Diamond" and a crooked stockbroker in Scorsese's "The Wolf of Wall Street," released in 2013.
Most Oscar pundits had expected him to win for Alejandro Iñárritu's "Revenant," an 1820s frontier drama that became famous for its arduous wintertime shoot -- and a brutal onscreen bear attack -- long before moviegoers ever saw the completed film. DiCaprio plays Hugh Glass, a fur trapper who survives the bear mauling and journeys hundreds of miles to seek revenge on the man who betrayed and abandoned him.
For one scene the actor ate a real raw bison liver -- a commitment that may have swayed academy voters.