The Izaak Walton League of America, Inc. is an American environmental organization founded in 1922 that promotes natural resource protection and outdoor recreation. The organization was founded in Chicago, Illinois, by a group of sportsmen who wished to protect fishing opportunities for future generations. They named the league after seminal fishing enthusiast Izaak Walton (1593–1683), known as the "Father of Flyfishing" and author of The Compleat Angler. Advertising executive Will Dilg became its first president and promoter. The first conservation organization with a mass membership, the League had over 100,000 supporters by 1924. An early result of their efforts was the establishment of the Upper Mississippi River National Wildlife and Fish Refuge in 1924. The League led unsuccessful efforts in the 1930s for clean water legislation but achieved initial success with the passage of federal water pollution acts in 1948 and 1956. Its major victory came with passage of the Clean Water Act of 1972. The League continues to advocate for preserving wetlands, protecting wilderness, and promoting soil and water conservation. Although the League's membership declined by the 1960s to a stable level around 50,000, the organization retains a firm base of conservationists and anglers nationwide, with more than 200 chapters across the country. The League publishes a quarterly magazine, Outdoor America, which covers the League's activities as well as the environment. They are headquartered in Gaithersburg, Maryland.