Thompson was incorporated in 1801, named for Matthew Thompson who came from Suffield, Connecticut.  The first settler was a Dr. Isaac Palmer from Plainfield, Connecticut who came to the area around 1800.

Mail service was established about 1823.  The first postmaster was George Emery, M.D. The first church building was a log house built in 1818 by the township at the north end of public square.  It was also used for the transaction of township business, and burned down in 1828.  The first grist mill was built in 1837 and burned in 1907.

In 1884 Chrysostom (Chrys) Sidley worked for Peter Gill who owned a stone quarry.  When Gill died, Sidley bought his equipment from the estate and opened as "Chrys Sidley, Bridge Builder and Contractor."  He built hundreds of bridges and culverts, large and small.

When people discovered that gravel made a good road surface, R.W. Sidley bought the Joe Strong farm and began a gravel business.  In 1932, he delivered gravel in a homemade trailer pulled by a Dodge roadster.  He bought his first truck in the fall of 1933.  He received 88 cents a load for his first truck delivery. Sixty-eight years later, R.W. Sidley is still going strong, and is one of the best-known businesses in the county.

The first radio in the county was made in 1918 by 11-year-old Floyd Murphy.  He made the radio with used batteries and coils from the Thompson Telephone Co., and with store-bought crystals. In 1947 he installed the first TV in the county.