Deadwood is a city that serves as county seat of Lawrence County, South Dakota, United States. It was named by early settlers after the dead trees found in its gulch. The city had its heyday from 1876 to 1879, after gold deposits had been discovered there, leading to the Black Hills Gold Rush. At its height, the city had a population of 25,000, attracting Old West figures such as Wyatt Earp, Calamity Jane, and Wild Bill Hickok.

Lawrence County is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 25,768, making it the 8th most populous county in South Dakota. Its county seat is Deadwood.