The major areas, including the incorporated towns which made up Haskell County, were definitely contained in Sans Bois County, Brooken, Lequire, Hoyt, Kanima, Enterprise, Cartersville, Star and other small rural communities. Prior to statehood, as far as " county seat "can be applied to the Choctaw form of government.  The Sans Bois county courthouse represented the only county seat (prior to statehood ) . During the transition of statehood and terms of the Constitutional Convention, Sans Bois County became Haskell County.

The Sans Bois Mountains, is situated in the southern portion of the county and two lakes,  the Robert S. Kerr Reservoir from the east and Lake Eufaula in the west, protrude into the county in the north. The Robert S. Kerr Reservoir,  has greatly benefitted the county, especially the town of Keota, making it a shipping point and attracting industry.

There is significance evidence that there existed presence of Caddoan-speaking Mound Builders ( approximately A.D. 850 - 1450 in the areas of the two rivers.  This has been documented by archaeological evidence.  The Choctaw, Witchita, Chicksaw, Osage and Quapaw hunted in this area of eastern Oklahoma before European contact.  In 1831 The Choctaws began arriving from there forced removal to the newly created Choctaw Nation, which included  Haskell County,  A few came by steamboat and landed at Tamaha.

As statehood approached the Choctaw government dealt with allotment, losing  the rights to its Segregated Coal Lands and lastly its right to self-government, Chief Greenwood McCurtain held the office of principle chief.  Chief McCurtain, the last of the three McCurtain brothers, the last to hold this important position, lived and made his headquarters at Sans Bois, in southern Haskell County. When Chief McCurtain's term expired in 1904, he was appointed as lifetime chief by President Theodore Roosevelt and served after statehood in 1907 until his death on December 27, 1910.