Benjamin Franklin (Frank) Hardin, surveyor, soldier, and legislator, the fourth son of Swan and Jerusha (Blackburn) Hardin, was born in Franklin County, Georgia, on January 25, 1803, and grew up in Maury County, Tennessee. He moved to Texas in 1826 and served under Stephen F. Austin against the Fredonian Rebellion of 1827. Hardin, who discontinued writing his first name in later years, was one of the Hardin brothers who, with their father, escaped into Texas after their feud with a prominent family in Maury County left two dead. Because their adversaries held various offices there, including one who was prosecuting attorney, the Hardins thought they would not receive a fair trail for murder; nevertheless, the Tennessee governor managed to have Franklin arrested and held at La Bahía (present Goliad), Texas, but when Tennessee officers failed to come for him, he was released, and he and his brothers were free to continue their services in Texas.
Hardin was elected secretary of the ayuntamiento of Liberty in 1831 and was surveyor of the Atascosita District from 1834 to 1836. He was first lieutenant of infantry and fought in the siege of Bexar under Col. Francis White Johnson. Hardin served as a lieutenant in Capt. William M. Logan's company until June 1836. He carried the San Jacinto victory dispatch for Sam Houston to the United States border. Between July 7, 1836, and October 7, 1836, he was captain of a newly organized company and joined an expedition against the Indians. Hardin was put in charge of guarding Mexican officers interned at his brother's plantation until they were repatriated in 1837. He was Liberty county surveyor (1838–45) and served as colonel of the Second Brigade of the Texas militia (1842–43). In 1839 he was appointed postmaster by Sam Houston and moved his family from his plantation north of Liberty to a house in town, known as Seven Pines, where he lived with his wife and six children and a slave known as Aunt Harriet. Harriet had moved to Texas with the Hardins in 1826 and lived to be nearly 100 years old.
Hardin continued to live near Liberty, where he was district surveyor from 1849 to 1852. He served in the Texas legislature in 1857, when Hardin County was formed from Liberty County and named in honor of the Hardin family. In the legislature he helped to get a surveyors' bill passed and the University of Texas founded and served as chairman of the Public Lands Committee.
He married Cynthia O'Brien in 1839; they had six children. Hardin was a Methodist. He died at his residence in Liberty on April 21, 1878. State historical markers were placed at the Hardin family cemetery in 1936 and the Liberty home site, Seven Pines, in 1988.