John Treadwell (November 23, 1745 – August 18, 1823) was an American politician and the 21st Governor of Connecticut.

[3] Treadwell unsuccessfully ran for Connecticut's at-large congressional district at least 5 times between 1788 and 1800[4], with his best performance coming in the September 1797 special election where he was a distant runner-up to William Edmond.

During his term, the Hartford Fire Insurance Company was proposed, and the Non-Intercourse Act was reinstated in February 1811, which resulted from Connecticut's opposition to the United States's impending war with Great Britain.

He was a member of the 1818 Constitutional Convention and also served on the American Board of Commissioners for Foreign Missions.

[6] Treadwell, a Congregationalist, died in Farmington, Hartford County, Connecticut, on August 18, 1823 (age 77 years, 268 days).