The Woman's Christian Temperance Union (WCTU) is an international temperance organization. It was among the first organizations of women devoted to social reform with a program that "linked the religious and the secular through concerted and far-reaching reform strategies based on applied Christianity." It plays an influential role in the temperance movement. Originating among women in the United States Prohibition movement, the organization supported the Eighteenth Amendment and was also influential in social reform issues that came to prominence in the Progressive Era.
The WCTU was originally organized on December 23, 1873, in Hillsboro, Ohio, and, starting on December 26, Matilda Gilruth Carpenter led a successful campaign to close saloons in Washington Court House, Ohio. WCTU was officially declared at a national convention in Cleveland, Ohio, November 18–20, 1874.