In September 1857, Cumming and about 1,500 federal troops were about a month from reaching Fort Bridger, 100 miles northeast of Salt Lake City. Young, desperately needing time to prepare an evacuation of the city, mobilized the Utah militia to delay the Army. Over several weeks, militiamen raided the troops' supplies, burned the grass to deny forage to the soldiers' horses, cattle and mules, even burned Fort Bridger. November snowstorms intervened. Snowbound and lacking supplies, the troops' commander, Col. Albert Sidney Johnston, decided to spend the winter at what was left of the fort. The Mormons, he declared, have "placed themselves in rebellion against the Union, and entertain the insane design of establishing a form of government thoroughly despotic, and utterly repugnant to our institutions." As the spring thaw began in 1858, Johnston prepared to receive reinforcements that would bring his force to almost 5,000—a third of the entire U.S. Army. At the same time, Young initiated what has become known as the Move South, an exodus of some 30,000 people from settlements in northern Utah. Before leaving Salt Lake City, Mormons buried the foundation of their temple, their most sacred building, and planted wheat to camouflage it from the invaders' eyes. A few men remained behind, ready to put houses and barns and orchards to the torch to keep them out of the soldiers' hands. The Mormons, it seemed, would be exterminated or once again driven from their land.
That they were neither is due largely to the intervention of their advocate Thomas Kane. Over the winter of 1857-58, Kane had set out for Utah to try to mediate what was being called "the Mormon crisis." Although his fellow Pennsylvanian President Buchanan did not provide official backing, neither did he discourage Kane's efforts. Kane arrived in Salt Lake City in February 1858. By April, in exchange for peace, he had secured Young's agreement to give way to the new governor. Many in the public, given Buchanan's failure to notify Young and the Army's delayed arrival in Utah, began to perceive the Utah expedition as an expensive blunder undertaken just as a financial panic had roiled the nation's economy. Buchanan, seeing a chance to end his embarrassment quickly, sent a peace commission west with the offer of a pardon for Utah citizens who would submit to federal laws. Young accepted the offer that June.That same month, Johnston and his troops marched through the deserted streets of Salt Lake City—then kept marching 40 miles south to establish Camp Floyd, in present-day Fairfield, Utah. With the Army no longer a threat, the Mormons returned to their homes.