Deadwood started illegally, as its location was at the time in Native American territory. The Treaty of Laramie of 1868 had guaranteed ownership of the Black Hills to the Lakota people. However, in 1874, Colonel George Armstrong Custer led an expedition into the Hills and announced the discovery of gold on French Creek near present-day Custer, South Dakota. Custer's announcement triggered the Black Hills Gold Rush and gave rise to the lawless town of Deadwood, which quickly reached a population of around 5,000.