The 1838 Mormon War in Missouri: Causes, Conflict, and Forced Exodus

The 1838 Mormon War was not a formal military conflict but a sustained campaign of violence, legal persecution, and forced removal that drove the Church of Jesus Christ of Latter-day Saints (LDS) and roughly 12,000 of its members out of Missouri between 1837 and 1839. It began as a clash between Mormon settlers and their non-Mormon neighbors over land, voting power, and religious difference, and escalated into armed militia raids, property destruction, and a gubernatorial order to expel or exterminate Mormons from the state. The conflict was rooted in genuine economic and political anxiety among Missourians, but also in religious bigotry and mob violence that went largely unpunished.

Why Mormons Came to Missouri—and Why Locals Resisted

Joseph Smith and early Mormon leaders believed Missouri—specifically Jackson County—was the biblical 'Zion,' a place where the faithful should gather and build a religious commonwealth. Starting in 1831, Mormons began buying land and settling in small numbers, but their arrival triggered immediate tension. Non-Mormon Missourians (often called 'Gentiles' by the LDS) saw Mormons as outsiders with alien beliefs, communal economic practices, and an insularity that made them unassimilable. More concretely, Mormons voted as a bloc, giving them political leverage disproportionate to their numbers. They also bought up land aggressively, using pooled church resources to outbid locals. By the mid-1830s, Mormons owned significant acreage and were migrating in larger numbers, creating a visible Mormon enclave.

Locals feared that if Mormon immigration continued unchecked, they would lose political control of the county and the state. Mormon theology—which held that non-believers would be cursed or removed in the coming millennium—fed paranoia that Mormons intended to seize Missouri for themselves. These anxieties were not entirely irrational (Mormons did intend to build a separate religious society), but they were amplified by religious prejudice and fueled by inflammatory newspaper rhetoric and sermons from both sides.

The Escalation: Mob Violence and Mormon Retaliation

In 1833, non-Mormon mobs in Jackson County began attacking Mormon settlements, burning homes and a printing press, and driving Mormons north into Clay County. For a few years, an uneasy truce held, but as Mormon numbers swelled—partly through immigration from the East and partly through conversion of locals—tensions reignited. By 1836–1837, Mormons had established settlements in Caldwell and Davies counties as well, and again clashed with neighbors over land boundaries, voting rights, and religious supremacy.

In 1838, the conflict turned sharply violent. Mormon leaders, including Joseph Smith, began organizing militia units (the 'Danites' or 'Destroying Angels') to defend Mormon settlements and intimidate opponents. Non-Mormons responded with their own militia bands. Skirmishes erupted at Crooked River, Gallatin, and other locations. In August 1838, Mormons were prevented from voting in Davies County, sparking outrage. By fall, armed clashes had become frequent, and both sides accused the other of atrocities—real and exaggerated. A particularly brutal incident in October, the Haun's Mill massacre, saw non-Mormon militia kill approximately 17 Mormon settlers, including children, in a surprise dawn attack. The massacre hardened Mormon resolve to resist but also convinced state authorities that the conflict was spiraling out of control.

The Extermination Order and Forced Exodus

On October 27, 1838, Missouri Governor Lilburn Boggs issued an executive order declaring that Mormons 'must be treated as enemies and must be exterminated or driven from the state if necessary for the public good.' This order—one of the most extreme official acts against a religious minority in U.S. history—authorized state militia to attack Mormon settlements and force their evacuation. It was not technically a genocide order, but it gave legal cover to militia violence and made clear that the state would not protect Mormon rights.

Joseph Smith and other Mormon leaders were arrested and jailed on charges of treason and murder. Smith was imprisoned in Liberty Jail for months while negotiations occurred. Meanwhile, Mormon families were expelled from their homes, their property seized or destroyed. In the bitter winter of 1838–1839, thousands of Mormons—including women, children, and the elderly—were forced to flee Missouri on foot or in wagons, heading east toward Illinois. By early 1839, nearly all Mormons had left the state. Smith and other leaders eventually escaped custody and joined their followers in Illinois, where they established a new settlement called Nauvoo.

Why This Conflict Mattered Then—and Now

The Missouri War was a watershed moment for the LDS Church. It transformed Mormons from a scattered, relatively open community into a tight-knit, defensive, and increasingly separatist movement. Smith's imprisonment and the state-sanctioned violence convinced him that Mormons could not safely coexist with non-Mormons in mainstream American society. This belief shaped Mormon theology (including new doctrines of millennial conflict) and led to the later emphasis on gathering in isolated communities—eventually Utah. The conflict also established a pattern: whenever Mormons grew too visible or powerful in a region, local opposition would mobilize, leading to violence and expulsion. This cycle would repeat in Illinois (1844–1846) and shape Mormon westward migration.

For American religious history, the Missouri War illustrates the fragility of religious tolerance in early 19th-century America. Although the U.S. Constitution protected religious freedom, state governments and local mobs could effectively persecute unpopular sects with little federal intervention. The Boggs extermination order was never formally repealed until 1976—meaning it remained technically law for nearly 140 years. The conflict also reveals how economic competition (land, voting power) and cultural difference can fuel religious violence, and how both majority fears and minority defensiveness can escalate conflict into atrocity.

Sources

• Givens, Terryl L. 'The Viper on the Hearth: Mormons, Non-Mormons, and the Instruments of Violence in Antebellum America.' Oxford University Press, 1997.
• LeSueur, Stephen C. 'The 1838 Mormon War in Missouri.' University of Missouri Press, 1987.
• Crawley, Peter L. 'Parley P. Pratt: The Apostle Paul of Mormonism.' BYU Studies, 1992.
• Missouri State Archives. 'Governor Lilburn W. Boggs Executive Order.' October 27, 1838.