County History
Upshur County Was Created in 1846 and Named for a Cabinet Official
Texas established Upshur County on April 27, 1846, naming it for Abel Parker Upshur, the U.S. Secretary of State who died in a cannon accident in 1844.
Upshur County was created by the first Texas state legislature after Texas joined the Union. The county was named for Abel Parker Upshur, who served as Secretary of State under President John Tyler. Upshur died on February 28, 1844, during a cannon test aboard the USS Princeton.
Gilmer became the county seat in 1848. The county law required the seat to be near the geographic center and to be named Gilmer — after Thomas W. Gilmer, who also died in the Princeton accident. The county originally included land that is now Camp County and part of Gregg County.
Source to confirm: Handbook of Texas — Upshur County