Onesimus Evans, state representative, was born March 24, 1807, at Liberty, Smith County, Tennessee, son of Joseph and Margaret (Reed) Evans. By 1830 Onesimus Evans had moved to Madison County, Tennessee, and on February 23 married Eliza Elizabeth Wallace. Soon after Evans was in Fayetteville, Arkansas, and was among the town founders petitioning the United States Congress that a post office be established. Evans was a charter member of Fayetteville's chapter of the Masons and of its Primitive Baptist Church. From 1839 until 1841 he served as Fayetteville postmaster. From 1836 until 1840 he also served in the Arkansas State Senate representing Benton, Madison, and Washington counties.
In 1842 as a representative of Fayetteville merchant and slave owner Alfred Wallace, Onesimus Evans traveled to Detroit to guard fugitive slave Nelson Hackett as he was extradited from Canada to Arkansas. Hackett, whose extradition had been the result of two years of legal wrangling, managed to escape from Evans' guard with the help of sympathetic New Yorkers. Hackett was ultimately recaptured in Illinois and returned to Fayetteville where he could not be found when Canadian abolitionists inquired after him.
Onesimus Evans was also the president of the Fayetteville branch of the State Bank, established in 1837. In 1841 or 1842 operations at the bank were suspended when its officers came under suspicion of stealing some of the bank's funds. At the time the bank's records could not be found, although portions of the records were later uncovered in Arkansas' White River, an old stove, and a stable in Fayetteville. The records were not complete enough to discern the cause of the bank's problems, and by the time they had been recovered Evans and the other officers of the bank had moved to Texas.
In the mid-1840s Evans and his family settled near San Antonio, and in October of 1846 he served as the grand jury foreman of the county's first court. When the San Antonio Railroad was chartered in 1850 Onesimus Evans was listed as a member of the corporate board of directors. Evans represented Bexar, Comal, Medina, and Gillespie counties in the House of the Fourth Texas Legislature during 1851 and 1852. Onesimus and his partners, son-in-law Richard Austin Howard and Alexander A. Muncey, operated a general store in San Antonio until Evan's death following a short illness on October 6, 1855. Onesimus Evans is buried in Section D of the San Antonio City Cemetery.