Industrial hemp was widely grown in the United States from the Colonial Period until the mid-1800s. During that time, Kentucky established itself as the leading hemp producer in the U.S. After the Civil War, hemp production declined in Kentucky, as well as in other areas of the country. Production temporarily resumed as part of the war effort during World War II. However, once the war was over, acreages dwindled until U.S. production ended in 1958. However, the last couple of decades have brought a renewed interest in commercial hemp as an alternative or supplementary crop. As the pro-hemp movement has spread, a number of states, including Kentucky, have passed laws favoring its production, generally in connection with scientific, economic, and environmental research studies.