Patricia,
There were no County's in 1860-thru the war-They were four District's-all formed by 1855 lands Chickasaw buy from Choctaw. (1860 Slave Census shows all districts & Tribes)

As shown on the Chickasaw 1860 Slave census.
Pontotic,Pickens,Tishomigo,Panola started in/by 1856.
Annica Kemp (a Wf of Winchester Colbert)is sister of Jackson Kemp (Both had father of Levi Kemp and Nancy he died just after removal) of Kemp by Red River in Panola Distrit 1860 slave census. shows 61 slaves he acted as Pro-term Gov in 1865 for "Winchester" Colbert-- was in Texas they are brother in-laws.
Borders appox line choctaw nation.North below-S Canadian River (Pontotic Dist.)Appox. 10 miles E of present day StoneWall to E.Chickasha,Purell,also wynnewood,Sulphur East border;Choctaw nation straight line S appox 10 E of Stonewall to a few miles N of Emet.
Atoka Dist -Choctaw from S.Canadian to near Emet.
(Atoka,Wapanucka)
Map -Who's Who Amoung the Southern Indians.
Blue Dist- Choctaw-(Boggy Depot,Durant)
Panola Dist.-Chickasaw-(Emet,Mead,Colbert,& Kemp)