Earth Day is an annual event, celebrated on April 22, on which day events worldwide are held to demonstrate support for environmental protection. It was first celebrated in 1970, and is now coordinated globally by the Earth Day Network and celebrated in more than 192 countries each year.

In 1969 at a UNESCO Conference in San Francisco, peace activist John McConnell proposed a day to honor the Earth and the concept of peace, to first be celebrated on March 21, 1970, the first day of spring in the northern hemisphere. This day of nature’s equipoise was later sanctioned in a Proclamation written by McConnell and signed by Secretary General U Thant at the United Nations. A month later a separate Earth Day was founded by United States Senator Gaylord Nelson as an environmental teach-in first held on April 22, 1970. Nelson was later awarded the Presidential Medal of Freedom Award in recognition of his work. While this April 22 Earth Day was focused on the United States, an organization launched by Denis Hayes, who was the original national coordinator in 1970, took it international in 1990 and organized events in 141 nations.Numerous communities celebrate Earth Week, an entire week of activities focused on environmental issues.

In 1968, Morton Hilbert and the U.S. Public Health Service organized the Human Ecology Symposium, an environmental conference for students to hear from scientists about the effects of environmental degradation on human health. This was the beginning of Earth Day. For the next two years, Hilbert and students worked to plan the first Earth Day. In April 1970—along with a federal proclamation from U.S. Sen. Gaylord Nelson—the first Earth Day was held.

Project Survival, an early environmentalism-awareness education event, was held at Northwestern University on January 23, 1970. This was the first of several events held at university campuses across the United States in the lead-up to the first Earth Day. Also, Ralph Nader began talking about the importance of ecology in 1970.

Earth Day 1970

The first Earth Day family had participants and celebrants in two thousand colleges and universities, roughly ten thousand primary and secondary schools, and hundreds of communities across the United States. More importantly, it “brought 20 million Americans out into the spring sunshine for peaceful demonstrations in favor of environmental reform.” It now is observed in 192 countries, and coordinated by the nonprofit Earth Day Network, chaired by the first Earth Day