Buffalo County, now extinct, was created by the legislature of 1879, with the following boundaries: "Commencing where the north line of township 20 south, intersects the line of range 27 west, thence south along range line to its intersection with the north line of township 24 south; thence west along township line to where it intersects the east line of range 31 west; thence north along range line to where it intersects the north line of township 20, south; thence east to the place of beginning."

It was bounded on the north by Lane county, east by Ness and Hodgeman, south by Foote and west by Sequoyah and Scott counties. In 1881 the northern tier of townships was taken from Buffalo and added to Lane, the remainder being made a part of a new county called Gray, and later was taken to form Finney county.