He came to Somerset sometime before 1812, for in May 1812, he was one of a commission to supervise the building of a County Clerk’s office.
He was a lawyer and became a member of the state legislature in 1811 and 1812. In the War of 1812, he armed and equipped a company of the Second Regiment Kentucky Militia at his own expense and then commanded them. After the war, he served as a circuit court judge. He was elected as a Democrat-Republican to be a member of the Fifteenth and Sixteenth Congresses and served from March 1817 until his resignation in June 1820.
He returned to Somerset in July 1824, where he resumed his law practice and agricultural pursuits.
Like so many other early figures of Pulaski County history, Tunstal Quarles was an avid member of the Freemasons. Using funding from the National Freemason Association, Quarles was able to organize the first bank in Somerset, the Farmers Bank, and served as president from 1825 to 1827. Little else is known about the role of Tunstal Quarles in masonic lore.
Tunstal Quarles died in Somerset on November 26, 1856, and is interred in the old Baptist Cemetery.