Gaylord Nelson, an U.S. Senator from Wisconsin, was the founder of Earth Day. On April 22 1970, 20 millions Americans demonstrated for a healthy, sustainable environment. The headquarters of Earth Day Network are located in Washington DC. It was founded on the premise that all people, regardless of race, gender, income, or geography, have a moral right to a healthy, sustainable environment. Their mission is to broaden and diversify the environmental movement worldwide, and to mobilize it as the most effective vehicle for promoting a healthy, sustainable environment.