1838 Mormon War

The 1838 Mormon War, also known as the Missouri Mormon War, refers to a series of conflicts and civil unrest between Mormons (Latter Day Saints) and other residents of northwestern Missouri from August 6 to November 1, 1838, culminating in the forced relocation of the Mormons from the state.

The Latter Day Saint movement, founded in 1830 and based in Kirtland, Ohio, rapidly expanded in Missouri through organized migration. Mormons initially settled an outpost in Jackson County in 1831 but faced severe hostility leading to their violent eviction in 1833. In 1836, Caldwell County was established to accommodate displaced Mormons from Jackson County. Caldwell County became an important hub for early Mormonism, coexisting with Kirtland, Ohio until early 1838, when key leaders, including Joseph Smith, relocated to Missouri.

The rapid influx of Mormons caused friction with local residents, particularly as the community expanded into neighboring counties. Tensions escalated in August 1838 at an election brawl in Gallatin, Daviess County, where Mormons were obstructed from voting. By October, vigilance committees, formed to forcefully expel the Mormons from the region, began to target settlements in Daviess and Carroll counties. The Missouri Volunteer Militia was dispatched to quell the unrest, but eventually defected to join the expulsion efforts. Mormons retaliated by organizing their own armed groups, further exacerbating the conflict.

After the Battle of Crooked River in late October, Governor Lilburn Boggs—believing there to be a Mormon insurrection—ordered state troops that they “must be exterminated or driven from the state." Boggs faced significant backlash for his response to the conflict, and the resulting controversy significantly undermined his administration's political effectiveness. The war resulted in the deaths of 22 people, and the displacement of approximately 10,000 Mormons, most of whom sought refuge in Illinois.