Originally posted on April 12, 2016. Forty-six years ago, on April 22, 1970, the first Earth Day was inaugurated with “a national teach-in on the environment” by founder Gaylord Nelson, then a U.S. Senator from Wisconsin. This April 20-24, 2016, educational opportunities continue in Fond du Lac and Oshkosh. The public is invited to the following Earth Day events: