John J. Hardin, son of Martin D. Hardin, "lawyer, born in Frankfort, Kentucky, 6 January, 1810; died in Buena Vista, Mexico, 27 February, 1847, was educated at Transylvania university, studied law, and removed to Jacksonville, Illinois, where he practised his profession. For several years he was prosecuting attorney, and a member of the legislature in 1836-'42. In 1842 he was elected to congress as a Democrat, and served one term. He volunteered when the Mexican war began, was appointed colonel of the 1st Illinois regiment, and was killed on the second day of the battle of Buena Vista, while leading his men in the final charge." Edited Appletons Encyclopedia, Copyright © 2001 VirtualologyTM
Biographical Directory of the United States Congress: HARDIN, John J., (son of Martin Davis Hardin), a Representative from Illinois; born in Frankfort, Ky., January 6, 1810; pursued classical studies and was graduated from Transylvania University, Lexington, Ky.; studied law; was admitted to the bar in Kentucky in 1831 and commenced practice in Jacksonville, Morgan County, Ill.; served in the Illinois Militia during the Black Hawk War 1831-1832; was brigadier general in command during the Mormon trouble in Hancock County in 1844 and later attained the rank of major general; appointed prosecuting attorney of Morgan County in 1832; member of the State house of representatives 1836-1842; elected as a Whig to the Twenty-eighth Congress (March 4, 1843-March 3, 1845); was not a candidate for renomination in 1844; during the Mexican War recruited the First Regiment, Illinois Volunteer Infantry, of which he was commissioned colonel; was killed at the Battle of Buena Vista, Mexico, February 23, 1847; interment in City Cemetery (East), Jacksonville, Ill.