Graham County was one of thirty-four counties created by the legislature in 1867, which divided into counties all of the organized portion of the state east of range line 26W. It was named in honor of Captain L. Graham, Company D, Eighth Kansas Infantry, who was killed in action in Chickamauga, September 19, 1863. The area-comprising Graham County was originally occupied by the Comanche tribe of Indians.
Graham is in the second tier of counties from the Nebraska Line and the fourth tier from the Colorado line. The Legislature of 1867 laid out the boundaries of Graham County, thirty miles square, making it one of the few square counties and giving it an area of 900 square miles. Assessed valuation for 2007 was $57,134,503. 2007 population was 2896.