TIME: Before you got the script, how aware were you about conflict diamonds?
DiCaprio: I'd heard whisperings. It was certainly out there in the public about what conflict diamonds were, and how people suffered as a result of natural resources being taken out of Africa. But I never understood the full story until I got this script and started doing research. I was pretty horrified about what went on in Sierra Leone in the late 1990s and how diamonds funded these warlords. Amnesty International projected around four million people lost their lives as a result of these diamond sales.
You were never a big bling guy, though, right? I see you around Los Angeles, and it's baggy jeans, baseball cap, driving a Prius.
Nah, I never was into diamonds, but that isn't to say I've never bought one in my life ? I have.
Your character is a hard-boiled mercenary and diamond smuggler. I saw glimpses of Steve McQueen and even a bit of Gable in your portrayal. Was it my imagination, or did anything from long-ago Hollywood inform your character in this film?
The Treasure of The Sierra Madre. I love that movie, wow. It really is a masterpiece. I think it's Bogart's best role.
Bogart did most of his acting on a soundstage. For Blood Diamond you traveled to Africa and spent about six months there. How did that affect you?
Mozambique only recently has had an economic resurgence, since the country had been pretty devastated by civil war. There's an alarming AIDS rate something like three or four out of 10 people have HIV or AIDS. You can't help but being affected when you're in those locations and seeing that stuff face to face. It wears on you emotionally. In America, we can just continue living our lives and go through our daily routines and ignore stuff like that but when you're there on location and in those situations, it really affects you. What can I say Africa needs a lot of help and support.
What were the people like?
It's a resurging economy, but people are so happy with so little. Literally, they were dancing in the streets. They've had civil war there for so long and even with all the hardships that people have had to endure, they still dance on street corners with joy. It was pretty amazing to see how people kept such a positive attitude and energy about life. It was inspiring. It makes you come back to America and really not want to hear anyone's complaints.
You hung out with mercenaries and read quite a bit to learn about your character. What was most helpful?
I always pick and skim through these books but it's hard to find information you're looking for as an actor. I try to meet real people so I can pinpoint and ask them specific questions. When you're sitting in a bar with someone, it's a whole different dynamic than just sifting through a book finding little bits of information that rarely gives you what you need to know about a character.