A post office was established at the townsite in 1902, with William G. Brown as the postmaster.

An election to locate the county seat was held in June 1908, and resulted in a runoff between Arnett and Shattuck, Oklahoma.

[9] Shortly thereafter, development continued with the founding of two weekly newspapers the Ellis County Capital and the Arnett Leader[10] as well as lawyer offices, banks, real estate/loan shops, grocery stores, blacksmiths, and more operating there in the pre-World War I years.

[12] According to the United States Census Bureau, the town has a total area of 0.4 square miles (1.0 km2), all land.

[19] The Courthouse is on the National Register of Historic Places listings in Ellis County, Oklahoma.

[20] The remains of Grand, Oklahoma, included on the National Register of Historic Places listings in Ellis County, Oklahoma as Grand Town Site, is 14 miles south of Arnett.

[23] The post office closed September 30, 1943, and only building footings remain today.

[24] Fort Supply Reservoir and Cooper Wildlife Management Area are to the northwest.

[25] Lake Lloyd Vincent and the Ellis County Wildlife Management Area are to the southwest.