Hugh French was born on February 22, 1826, in Smith County, Tennessee, United States. He was the son of Colonel Daniel Thomason and his wife Mary Jane Denton. His father died in 1839, and he moved to Washington County, Arkansas, where he taught school in 1845.
Thomason studied law in 1846.
In 1847, Hugh French Thomason was admitted to the Arkansas bar. Thomason lived in Fayetteville from 1847 until 1861, when he moved to Van Buren in Crawford County, Arkansas. In 1851, he was prosecuting attorney for the Fayetteville Circuit.
In 1856, he ran unsuccessfully as an American party candidate for the United States House of Representatives.
During the second session of the state convention, he acquiesced on the secession issue. He was a delegate to the provisional Confederate Congress at Montgomery but was defeated by Felix Batson for election to the permanent Congress in 1861 because he had not been an original secessionist.
In Congress, he served on the Territorial Committee. After 1861, he took no further part in the war. However, as a state legislator in 1866, he offered a general amnesty bill for all ex-Confederates.
He was an Arkansas commissioner to Washington, D.C., during Reconstruction, and he joined the Democratic party in the late 1860s. In 1874, Thomason was a delegate to the state constitutional convention and ran unsuccessfully for Congress. From 1880 to 1886, he was a state senator.
Originally a Democrat, Thomason joined the Know-Nothings after the passage of the Kansas-Nebraska Act. He supported John Bell for the presidency in 1860.
Thomason was married twice: to Margaret Amanda Bostick and Fannie Rose Knox.
