Leonardo DiCaprio was born in Los Angeles, California and was raised a Roman Catholic, probably due to his German and Italian background.
DiCaprio (like many Catholics) isn't religious, but he's not an atheist. Based on this quote, maybe religion would do him some good:
Death freaks me out. I don't know about an afterlife. I'm not religious, you know. I'm not an atheist, but I've never had a religion.
Recently, DiCaprio was dating a Jewish woman by the name of Bar Refaeli and it was rumored he would convert to Judaism to marry her. They even took a trip to Israel but the couple split before that could happen.
Perhaps DiCaprio's alleged willingness to convert to Judaism and the fact that he is a "non-religious" Catholic would point to him being spiritually flexible. There is more evidence of that considering in 1998, as a result of exhaustion, DiCaprio entered a Buddhist center in Los Angeles to meditate and "recharge." He's also listed as a Buddhist on various celebrity religion sites.
Trying to stop a sinking ship
Leo's a hardcore Democrat. In 2008, he donated over $38,000 to the Democratic party including directly to then-candidate Barack Obama. So far, for the 2012 election cycle, Leo has donated at least $5,000 to Obama's re-election campaign.
DiCaprio is widely-known as a serious environmentalist. It seems, among the wide variety of liberal causes, that DiCaprio certainly puts the environment above the rest but acknowledging many other important issues., DiCaprio once said of the media's obsession with social issues like gay marriage:
That's the most infuriating thing–watching people focus on these things. Meanwhile, there's the onset of global warming and these incredibly scary and menacing things with the future of our economy. Our relationship to the rest of the world. And here we are focusing on this?
DiCaprio has certainly put his money where his mouth is (literally and figuratively) when it comes to the environment. DiCaprio is famous for his environmentally friendly cars, he has installed solar panels on his house, and he works with environmental organizations (and Al Gore) such as Global Green and the Natural Resources Defense Council.
He has had no issues with talking publicly about issues like global warming and his outspoken efforts once won him the VH1 Do Something Award.