The Mormon pioneers were members of The Church of Jesus Christ of Latter-day Saints (LDS Church), also known as Latter-day Saints, who migrated across the United States from the Midwest to the Salt Lake Valley in what is today the U.S. state of Utah. At the time of the cease fire and planning of the exodus in 1846, the territory was owned by the Republic of Mexico, which soon after went to war with the United States over the annexation of Texas. Salt Lake Valley became American territory as a result of this war.