The vast colonization of the Church of Jesus Christ of Latter-day Saints, or Mormons, in the nineteenth century had a profund impact on the populating, culture, economy, and environment of much of the American West. This thesis examines the political geographic influence of the Mormons in the West and, more specifically, in the lands ceded by Mexico to the United States in 1848. This land comprises all or portions of the following states: California, Nevada, Utah, Wyoming, Colorado, Arizona, and New Mexico.
The original organization of the Mexican Cession at the hands of Congress in 1850 was drastically influenced by the fact that the Mormons had decided to settle in the Great Basin. From this initial territorial organization in 1850 to the early years of the twentieth century, the boundaries of each of the aforementioned states were significantly influenced by two key factors: the Mormon presence in certain areas and the strained relationship between Congress and the Mormon Church. In many instances, state and territorial boundaries were drawn, modified, or even left alone as a direct result of one or often both of these factors. This thesis identifies and examines all of these boundary-making decisions.
In order to better illustrate the actual impact of the Mormons on the political geography of the West, two hypothetical scenarios are presented in the final chapter. In the first scenario, the author hypothesizes as to how the West might look today if the Mormons had not come West and settled there. In the second, a West is envisioned in which the relationship between the Mormons and Congress was not adversarial.



College and Department

Family, Home, and Social Sciences; Geography



Date Submitted


Document Type





Mormons, West, U.S., History, 19th century, Politics, government, Geography, Boundaries, State