Wallace County is a county located in the U.S. state of Kansas. Its county seat is Sharon Springs. As of the 2020 census, the county population was 1,512, making it the second-least populous county in Kansas. The county was created in 1868 and named in honor of Brigadier General W.H.L. Wallace, who had been mortally wounded in combat in the Battle of Shiloh. Wallace County is home to Mount Sunflower, the highest point in Kansas at 4,039 feet.