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Nelson, who passed away in 2005 at age 89, served as the governor of Wisconsin and, later, a three-term senator. Back in 1969, with the United States embroiled in the Vietnam War, Sen. Nelson witnessed the effects of a massive oil spill off the coast of Santa Barbara, California. He left determined to help.His goal, says EarthDay.org, was to harness the growing power of the antiwar movement and to "infuse that energy with an emerging public consciousness about air and water pollution." Sen. Nelson, a Democrat, didn't make it a partisan issue, recruiting Rep. Pete McClosksy, a Republican, to serve as his co-chair.
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The first Earth Day, on April 22, 1970, featured rallies and teach-ins across the United States. Roughly one in 10 Americans participated in Earth Day activities during its inaugural year.
Earth Day was particularly big with college students, but it went well beyond campus gates. According to EarthDay.org, the event had "support from Republicans and Democrats, rich and poor, city slickers and farmers, tycoons and labor leaders." In fact, the success of Earth Day spurred the creation of the Environmental Protection Agency. It also inspired landmark legislation like the Clean Air Act, the Clean Water Act, and the Endangered Species Act.
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Much of the movement's success can be attributed to Nelson's decision to encourage communities to act independently. He asked that anybody interested in Earth Day participate "in any way they want."
By 1990, more than 180 countries were participating in Earth Day. In the years since, the holiday has gone even more mainstream. With climate change and environmental disasters in the news on a daily basis, people think about the planet far more often than just one day a year.