In addition, parts of two neighboring cities cover land that was once part of the township: Brimfield Township covers a total area of 21.4 square miles (55 km2) of which 20.5 square miles (53 km2) is land.

It was formed from survey township Town 2, Range 9 of the Connecticut Western Reserve.

The original proprietors were Israel Thorndike of Boston and John Wyles of Hartford, Connecticut, both of whom came to the area in 1816 to view their land and divide it.

Brimfield was known by a succession of different names during the first few years, mostly in reference the swampy land within its borders.

[5] 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.