City, seat of Hancock county, western Illinois, U.S., near the Mississippi River. Laid out in 1833 and named for the ancient North African city, the community was hostile to the Mormons who had settled at nearby Nauvoo. On June 27, 1844, Joseph Smith, the founder of Mormonism, and his brother Hyrum, who were in the Carthage City Jail awaiting trial on charges of treason, were shot to death