writ of habeas corpus and made his way to Illinois, where he joined the main body of Mormon refugees in 1839. In 1844, Smith, and his brother, Hyrum, were killed by a mob while in custody in the city of Carthage, Illinois. In 1846, religious tensions reached their peak, and in 1848 mobs burned the Latter-day Saint temple in Nauvoo. According to church belief, God inspired Brigham Young (Joseph Smith's successor as church president) to call for the Saints (as church members call themselves) to organize and head West, beyond the western frontier of the United States (into what was then Mexico, though the U.S. Army had already captured Santa Fe de Nuevo México and the colonized parts of Alta California in late 1846). During the winter of 1846–1847, Latter-day Saint leaders in Winter Quarters and Iowa laid plans for the migration of the large number of Saints, their equipment, and their livestock. It was here that Young first met Thomas L. Kane, a non-Mormon from Philadelphia with deep personal connections to the Polk administration. Kane obtained permission for the Mormons to winter on Indian territory, and the site was originally called Kanesville. Young continued to trust Kane throughout his own lifetime, particularly as an intermediary with the often hostile Federal government. This major undertaking was a significant test of leadership capability and the existing administrative network of the recently restructured church. For his role in the migration, Brigham Young is sometimes referred to as the "American Moses." Young personally reviewed all available information on the Salt Lake Valley and the Great Basin, consulting with mountain men and trappers who traveled through Winter Quarters, and meeting with Father Pierre-Jean De Smet, a Jesuit missionary familiar with the Great Basin. The wary Young insisted the Mormons should settle in a location no other colonizers wanted, and felt the Salt Lake Valley met that requirement but would provide the Saints with many advantages as well. Vanguard company of 1847 Young organized a vanguard company to break the trail west to the Rocky Mountains, gather information about trail conditions, including water sources and Native American tribes, and to ultimately select the central gathering point in the Great Basin. The initial company would select and break the primary trail with the expectation that later pioneers would maintain and improve it. It was hoped that the group could, wherever possible, establish fords and ferries and