Greenbelt is a city in Prince George's County, Maryland, United States, and a suburb of Washington, D.C. At the 2020 census, the populatio…Greenbelt is a city in Prince George's County, Maryland, United States, and a suburb of Washington, D.C. At the 2020 census, the population was 24,921. Greenbelt is the first and the largest of the three experimental and controversial New Deal Greenbelt Towns, the others being Greenhills, Ohio, and Greendale, Wisconsin. Greenbelt was planned and built by the federal government as an all-white town. The cooperative community was conceived in 1935 by Undersecretary of Agriculture Rexford Guy Tugwell, whose perceived collectivist ideology attracted opposition to the Greenbelt Towns project throughout its short duration. The project came into legal existence on April 8, 1935, when Congress passed the Emergency Relief Appropriation Act of 1935. Under the authority granted to him by this legislation, President Franklin D. Roosevelt issued an executive order, on May 1, 1935, establishing the United States Resettlement Administration.