Harpersville is a town in Shelby County, Alabama, United States. It is notorious for being the birthplace of the founder of the modern KKK, William Joseph Simmons. According to the 1950 U.S. Census, it formally incorporated in 1943. At the 2010 census, the population was 1,637, up from 1,620 in 2000. It is located southeast of the Birmingham metro area.