The 2020 census found 5,743 people in the township.

[3] Located in the western part of the county, it borders the following townships: The village of Barnesville is located in central Warren Township.

[5] In 1833, several gristmills and saw mills were being operating in Warren Township, powered by the waters of Captina Creek and the Stillwater River.

[6] The township is governed by a three-member board of trustees, who are elected in November of odd-numbered years to a four-year term beginning on the following January 1.

There is also an elected township fiscal officer,[7] who serves a four-year term beginning on April 1 of the year after the election, which is held in November of the year before the presidential election.