John Tester

John A. Tester (March 30, 1835 – May 26, 1918) was an American merchant who served as a Republican member of the Wisconsin State Assembly from Buffalo County, Wisconsin in 1883. He was succeeded by Samuel Decius Hubbard.

Born in Rongellen, the Canton of Grisons, Switzerland, Tester moved with his parents to St. Louis, Missouri in 1848 and then to Wisconsin in 1853. He served in the 6th Wisconsin Volunteer Infantry Regiment as first lieutenant during the American Civil War. He served as deputy county treasurer for Buffalo County, Wisconsin and on the Buffalo County Board of Supervisors. He also served on the Alma, Wisconsin village board as trustee and as president.