Iron Eyes Cody was most famous for his "crying Indian" role in the
"Keep America Beautiful" Public Service Announcement (PSA) in the early 1970s. It was an ecology commercial in which an Indian (Cody) sheds a tear after some trash is thrown from a speeding car and lands at his feet. The announcer, William Conrad, of Bullwinkle and Cannon fame, memorably declares: "People start pollution; people can stop it."
Earth Day, the annual day of environmental action and awareness,
was first held 4 months before I was born on April 22, 1970.
So, Chief Iron Eyes Cody wasn't a real Native American after all. That didn't stop the ad campaign from having a tremendous effect back then. And it's no less relevant today.
Here are some links to check out:
http://en.wikipedia.org/wiki/Earth_Day
http://www.kab.org/