The Darlington County Library System can trace its roots back to the early 1880s. Captain Henry Thompson started the Darlington Guards Library for the use of guard members and their families. Later, access was granted to any gentleman of the community and two ladies of his choice, for a small fee.
In 1912, the library was donated to the Civic League, a public service-oriented group of women. By 1922, an expansion was needed, and renovations were made. A large addition was planned in 1928, but was put on hold by bank failure and the Depression. The WPA helped the library double its size in 1933-34.
Largely due to the Farm Women Council, bookmobile service was added in 1936. The Darlington and Hartsville libraries merged in 1968 to form the Darlington County Library System, with added service in the historic Society Hill Library (1822) and the Lamar Library. The Darlington County Library has been in its current location, 204 N. Main Street, since March 1988.