Robert Frederick Smith was born on August 2, 1806, in Philadelphia, Pennsylvania. He moved to Hancock County, Illinois, in 1833. He married Amanda Benton there on June 19, 1834, and they had at least fourteen children: Emma, born around 1835; Louisa, born around 1838; John, born around 1838; George, born around 1841; Robert, born around 1842; Henry, born around 1844; Mary, born around 1845; Clarissa, born around 1847; Franklin, born around 1848; Annette, born around 1849; Horatio, born around 1852; Alexander, born around 1854; Elinor, born around 1855; and Cora, born around 1859.
As one writer later recalled, he was “captain of the Carthage Greys, and was in charge of that company on guard at the old Carthage jail on June 27, 1844, when the Mormon prophet, Joseph Smith, was killed by a mob after overpowering the militia. He had command of the military organization during the Mormon war in Hancock county, and was wounded in the Battle of Nauvoo in September, 18[4]6.” He also served in the Mexican-American War. He worked as a farmer, and by 1850, he owned $1,600 of real estate. A decade later, he owned $6,000 of real estate and $1,300 of personal property.
In May 1861, Smith received a commission as a colonel of the 16th Illinois Infantry. The regiment took part in the Atlanta campaign. He was eventually promoted to brigadier general, and he mustered out on July 8, 1865.
Smith returned to Hancock County after the war. By 1870, he owned $8,550 of real estate and $1,570 of personal property. He died in Hamilton, Illinois, on April 25, 1893.