Gladstone is a village in Henderson County, Illinois, United States. The population was 234 at the 2020 census. It is part of the Burlington, IA–IL Micropolitan Statistical Area. Gladstone is located in west-central Henderson County. Illinois Route 164 passes through the village, leading north 5 miles to Oquawka, the county seat, and south 1 mile to U.S. …Gladstone is a village in Henderson County, Illinois, United States. The population was 234 at the 2020 census. It is part of the Burlington, IA–IL Micropolitan Statistical Area. Gladstone is located in west-central Henderson County. Illinois Route 164 passes through the village, leading north 5 miles to Oquawka, the county seat, and south 1 mile to U.S. Route 34. Burlington, Iowa, is 10 miles southwest of Gladstone via IL-164 and US-34.