He was active in opposing the presence of the Latter Day Saints in Hancock County, Illinois, during the 1840s.
He is one of five defendants who were tried and acquitted of the 1844 murder of Joseph Smith, founder of the Latter Day Saint movement.
When Latter Day Saints began settling in Hancock County in the late 1830s and early 1840s, Williams became a fierce opponent of their presence.
In 1843, Williams led a militia that captured Mormon Daniel Avery and his son and threatened them with guns and knives before releasing them in Missouri.
According to "Wild Bill" Hickman, Williams told him that because the Mormons "ruled the county [and] elected whom they pleased ... the old settlers had no chance".