He was one of a large family of Hugh Dunlap and Susanna Gilliam, the sons all lawyers.
After serving in the Indian campaign in 1818 and 1819, Dunlap moved to Bolivar, Tennessee in 1828.
Dunlap was a judge of the Eleventh Circuit Court of Tennessee from 1840 to 1849, when he resigned and resumed practicing law.
Dunlap Street near the medical center in Memphis, TN is also named for him.
Dunlap died near Memphis, Tennessee on November 16, 1872 (age 74 years, 265 days).