While the area was still a part of Plainfield Township, the settlement at Cannonsburg was founded in 1842 on an old Native American trail (Chippewa and Ottawa populated the area prior to the region being opened for white settlers). In 1844 and 1845, mills were erected by Edwin B. Bostwick, with H.T. Judson as architect.
As an inducement to settlement, the community was platted in 1848 (or 1845 by some accounts). Bostwick, a business agent of railroad and steamboat financier LeGrand Cannon of Troy, New York, was instructed to give a lot to each resident who was not otherwise provided for. Twenty-five lots were given away and the town was named in honor of Cannon, who acknowledged the honor with the gift of a small cannon engraved with his name and the date.
The first record of the township separate from Plainfield is on April 6, 1846. Mention is made that the Michigan Legislature had organized the town under the name of "Churchtown" in the spring of 1846 (or 1845 in some sources). The name was soon after changed to Cannon, after the largest settlement.
A post office was established on May 7, 1844, with the spelling as "Cannonsburgh". The spelling was changed to Cannonsburg on February 5, 1894. The Cannonsburg ZIP code 49317 provides P.O. Box only service. Cannonsburg continued to be at the center of township business through the end of the 20th Century when the township offices were moved to a new location 2 miles to the north, along the M-44 corridor.