Hancock County, Illinois, became the site of a dramatic experiment in religious self-government and, after Joseph Smith’s murder, a landscape of escalating conflict. Its river settlement of Nauvoo grew rapidly into a major Mormon center, but the violence of 1845 and an agreement to leave the United States turned the county into the Saints’ point of departure for their migration west.

Nauvoo’s Rise on the Mississippi

A month after escaping jail in Missouri, Joseph Smith surveyed a bend in the Mississippi River in Hancock County and chose it as the site for a capital of the Kingdom of God. The low-lying eastern-bank ground was so wet that travel across it was difficult, and ox teams could not pass. Yet it was nearly uninhabited, and its owner was willing to sell land on credit. Construction began, and within five years more than 15,000 Saints lived in and around Nauvoo—about ten times the town’s present population at the time of the account. It became Illinois’s second-largest municipality, a city built from a malarial swamp that rivaled Chicago.

Nauvoo’s growth was also a concentration of authority. A charter passed by the Illinois General Assembly in December 1840 granted the city unusual sovereign rights and powers. Under Joseph Smith, it functioned as a theocratic principality: he was formally anointed as a ruler over Israel, commanded the disciplined Nauvoo Legion, and sought authorization from the U.S. Congress for a 100,000-man force under his personal control. Congress rejected that request. In January 1844, Joseph Smith announced his candidacy for president, extending his political ambitions beyond the county and the city.

Trials and Rising Violence

After Joseph Smith and Hyrum Smith were murdered, the county became the setting for a contested attempt to bring their killers to trial. In May 1845, nine men were indicted; seven were brought to trial in Carthage in the case known as People v. Levi Williams. The defendants included prominent local figures, among them officers of the Carthage Greys, a state senator, and the editor of the Warsaw newspaper. John Taylor and Willard Richards, Mormon apostles who had witnessed the murders, refused to appear, fearing they would be killed if they came near Carthage. On May 30, the defendants were found not guilty. The verdict angered the Mormons, who had expected it but regarded the outcome as a failure of earthly justice.

Violence against Mormon residents intensified through the summer. Anti-Mormon vigilantes led by Levi Williams burned Mormon homes and farms; by September 15, forty-four residences had been destroyed. The next day, Porter Rockwell encountered Frank Worrell, a Carthage Greys officer who had guarded the jail on the night of the murders, and shot him. A few days later, Mormons killed a young Gentile man suspected of burning homes. These retaliatory acts deepened the conflict rather than ending it. Posses from both sides ranged across the county, setting fires and plundering property; more than two hundred homes were burned.

Agreement to Leave and the Exodus

Fearing that Hancock County was again nearing civil war, Governor Thomas Ford sent 400 troops to Nauvoo with a committee of dignitaries, including Stephen A. Douglas, to negotiate an end to the hostilities. On September 24, Brigham Young offered a cease-fire agreement under which the Mormons would leave Illinois and the United States the following spring. The Gentiles accepted the proposal on October 1, giving the Saints a period of relative calm to build wagons and gather supplies.

Brigham Young sought a new home far from established settlements, in a place that would seem unattractive to Gentile newcomers. After considering Oregon, California, and Vancouver Island, he and his counselors chose the sparsely inhabited Great Basin, then part of Mexico. The Saints had planned to wait for warmer weather before leaving Nauvoo, but a warrant for Brigham Young’s arrest on charges of harboring counterfeiters prompted an earlier departure. On February 4, 1846, the first group crossed the Mississippi River by flatboat to the Iowa shore, beginning the migration west. Hancock County’s story thus turns from the creation of a powerful Mormon city to the conflict that made its abandonment seem necessary.