Earth Day, April 22, each year marks the anniversary of the birth of the modern environmental movement in 1970.

Among other things, 1970 in the United States brought with it the Kent State shootings, the advent of fiber optics, "Bridge Over Troubled Water," Apollo 13, the Beatles' last album, the death of Jimi Hendrix, the birth of Mariah Carey, and the meltdown of fuel rods in the Savannah River nuclear plant near Aiken, South Carolina -- an incident not acknowledged for 18 years.

It was into such a world that the very first Earth Day was born.

Earth Day founder Gaylord Nelson, then a US Senator from Wisconsin, proposed the first nationwide environmental protest "to shake up the political establishment and force this issue onto the national agenda." "It was a gamble," he recalls, "but it worked."

At the time, Americans were slurping leaded gas through massive V8 sedans. Industry belched out smoke and sludge with little fear of legal consequences or bad press. Air pollution was commonly accepted as the smell of prosperity. Environment was a word that appeared more often in spelling bees than on the evening news.

Earth Day 1970 turned that all around.

On April 22, 20 million Americans took to the streets, parks, and auditoriums to demonstrate for a healthy, sustainable environment. Denis Hayes, the national coordinator, and his youthful staff organized massive coast-to-coast rallies. Thousands of colleges and universities organized protests against the deterioration of the environment. Groups that had been fighting against oil spills, polluting factories and power plants, raw sewage, toxic dumps, pesticides, freeways, the loss of wilderness, and the extinction of wildlife suddenly realized they shared common values.

Denis Hayes - Honorary Chair, Earth Day Network

Earth Day 1970 achieved a rare political alignment, enlisting support from Republicans and Democrats, rich and poor, city slickers and farmers, tycoons and labor leaders. The first Earth Day led to the creation of the United States Environmental Protection Agency and the passage of the Clean Air, Clean Water, and Endangered Species acts.

Sen. Nelson was awarded the Presidential Medal of Freedom -- the highest honor given to civilians in the United States -- for his role as Earth Day founder.

As 1990 approached, a group of environmental leaders asked Denis Hayes to organize another big campaign. This time, Earth Day went global, mobilizing 200 million people in 141 countries and lifting the status of environmental issues on to the world stage. Earth Day 1990 gave a huge boost to recycling efforts worldwide and helped pave the way for the 1992 United Nations Earth Summit in Rio de Janeiro.

As the millennium approached, Hayes agreed to spearhead another campaign, this time focused on global warming and a push for clean energy. Earth Day 2000 combined the big-picture feistiness of the first Earth Day with the international grassroots activism of Earth Day 1990. For 2000, Earth Day had the Internet to help link activists around the world. By the time April 22 rolled around, 5,000 environmental groups around the world were on board, reaching out to hundreds of millions of people in a record 184 countries. Events varied: A talking drum chain traveled from village to village in Gabon, Africa, for example, while hundreds of thousands of people gathered on the National Mall in Washington, D.C., USA.

Earth Day 2000 sent the message loud and clear that citizens the world 'round wanted quick and decisive action on clean energy.

Now, the fight for a clean environment continues. We invite you to be a part of this history and a part of Earth Day. Discover energy you didn't even know you had. Feel it rumble through the grass roots under your feet and the technology at your fingertips. Channel it into building a clean, healthy, diverse world for generations to come.

(Earth Day Network April 20, 2009)