On January 3, 1809, the Ohio government authorized the creation of Darke County. Residents named the county in honor of General William Darke, a hero of the American Revolution. In 1795, General Anthony Wayne and the chiefs of thirteen Native American tribes signed the Treaty of Greeneville, forcing the natives to move to the northwestern corner of what would become Ohio. The sides signed the treaty at Fort Greene Ville, located in modern-day Darke County.
Darke County is located in the western part of Ohio. Its western border helps form the boundary between Ohio and Indiana. The county seat is Greenville, which is the largest city in the county with a population of 13,294 people in 2000. Approximately eighty-five percent of Darke County's six hundred square miles are covered in farms. Only 1.3 percent of the county is deemed to be urban. The county averages almost eighty-nine people living in each square mile. Between 1995 and 2000, the county experienced a three-tenths of one percent drop in population, a trend that holds true for many of Ohio's more rural counties, as residents seek better opportunities in the state's larger cities. In 2000, the county's residents numbered 53,309 people.
Most of Darke County's residents find employment in agricultural positions. In the state, the county ranks first in corn and soybean production and second in hog raising. Manufacturing, retail, and service positions finish second, third, and fourth respectively. In 1999, the per capita income was 23,678 dollars, with just over seven percent of the county's residents living below the poverty level.
Most voters in Darke County claim to be independents, yet in recent years, they have overwhelmingly supported Republican Party candidates at the national level.
Markswoman Annie Oakley ranks among the county's more famous residents. She is buried near Brock, Ohio.