1. The data considered here are restricted to those individuals who were assigned to a wagon or handcart company. Those individuals who died immigrating prior to being identified with a company, for example those dying prior to reaching a staging area such as Florence, Kanesville, Mormon Grove, etc., or those dying at the staging area before being assigned to a company, are not included.

2. The transcontinental railroad was completed in 1869, materially altering the manner in which many immigrated.

3. “Special-interest publications” refer to church articles, advertisements, and reports by groups who may have a special interest in downplaying the health and mortality risks of crossing the plains.

4. The articles appeared almost monthly between 1891 and 1893 in the Contributor, vols. 12, 13, and 14.

5. See Andrew Jenson, “Church Emigration Book,” vol. 1, [p. 2], Church History Library, The Church of Jesus Christ of Latter-day Saints, Salt Lake City. Although his estimate was couched in the context of immigrants crossing the plains, Jenson gave no further details about how he determined this number or about his perception of the journey. A recent attempt to assess Mormon migration deaths clearly shows that Jenson took a broad view of determining the number of deaths. His death tally included those who traveled on ships, riverboats, railroads, in wagon and handcart companies, and while in transit at outfitting places or way stations; in other words, the entire breadth and spectrum of immigrant migration—not just those crossing the plains. He may have even included deaths of people who halted in Missouri or Iowa or in any place of Mormon gathering for an extended period of time. He also included deaths beyond 1868.

6. See Wallace Stegner, The Gathering of Zion (New York: McGraw-Hill, 1964), 9n, citing sources for 46,972 to 68,028. Leonard J. Arrington, Great Basin Kingdom (Cambridge, Mass.: Harvard University Press, 1958), 99: “more than 51,000 Mormon emigrants had been assisted to America, of whom 38,000 were British, and over 13,000 were from the Continent and Scandinavia,” thus not including Americans. Jenson, “Church Emigration Book,” vol. 1, [p. 2]: “We approximate that 80,000 L.D.S. emigrants crossed the Plains in Pioneer years.” Arnold K. Garr, Donald Q. Cannon, and Richard O. Cowan, Encyclopedia of Latter-day Saint History (Salt Lake City: Deseret Book, 2000), 415: “more than 60,000.”

7. Susan E. Black and others, “Do We Know How Many Latter-day Saints Died between 1846 and 1869 in the Migration to the Salt Lake Valley?” Ensign 28 (July 1998): 40–44. See also Shane A. Baker, “Illness and Mortality in Nineteenth-Century Mormon Immigration,” Mormon Historical Studies 2, no. 2 (2001): 77–90, which discusses causes of death.

8. It has been suggested that since these data are based on individual enumeration, or “counting heads,” these counts are conservative (underestimate the actual numbers). Some believe that there are a considerable number of people who crossed the plains to Utah who left no documentary record. William Hartley, private communication to Melvin Bashore. Here we focus on the experience of the 56,042.

9. Peter D. Olch, “Treading the Elephant’s Tail: Medical Problems on the Overland Trails,” Overland Journal 6, no. 1 (1988): 25–31.

10. Personal communication from geographer Richard L. Reick. Reick revises those overland death rates downward, below the Mormon death rate. Dr. Reick’s data have yet to be published.

11. Jill N. Crandell, “Garden Grove, Iowa: From Mormon Way Station to Permanent Settlement 1846–1852” (master’s thesis, Brigham Young University, 2010); Richard E. Bennett, Mormons at the Missouri, 1846–1852: “And Should We Die” (Norman: University of Oklahoma Press, 1987); Evan L. Ivie and Douglas C. Heiner, “Deaths in Early Nauvoo, 1839–46, and Winter Quarters, 1846–48,” Religious Educator 10, no. 3 (2009): 163–73.

12. Melvin Bashore initiated and followed through on this effort, doing intensive work from about 1998 to 2003 and then adding new information until his retirement in 2013. There were several service missionaries who helped with this labor-intensive effort.

13. Deaths that occur between the date of arrival and the end of that year are included in the current analysis as deaths on the trail. There are two reasons for this. First, for many deaths we only have the year and not the month of death. Second, deaths that occur soon after arriving may be attributable to the crossing.

14. Additional information included cause of death, name of parents, burial place, and so forth.

15. Melvin Bashore and the volunteer team have identified more individuals who are not in the data files searched here. These additional counts will add to the big picture but will probably not materially change the observed patterns reported here. These have not been included because there is some uncertainty or incompleteness about the record.

16. By “relative numbers” we mean that if we had randomly drawn 55,662 individuals (the subset of the 56,042 individuals for whom we know their sex) from the U.S. white population in 1850, with the same number of males and females as in the Mormon immigration, we would expect to get the total age counts in these figures. U.S. population was obtained from the data file nhgis0001_ds10_1850_state, located at https://www.nhgis.org.

17. Herbert S. Klein, A Population History of the United States (Cambridge, U.K.: Cambridge University Press, 2004), 100–101, citing McClelland and Zeckhauser, Demographic Dimensions of the New Republic, 109.

18. Age-specific mortality rates were obtained from Michael R. Haines, Estimated Life Tables for the United States, 1850–1900, NBER Working Paper, historical paper no. 59 (Cambridge, Mass.: National Bureau of Economic Research, 1994), males 1860 and females 1860, available at http://www.nber.org/papers/h0059.pdf.

19. We multiplied the U.S. rates by seven-twelfths to correlate with the fact that the mortality data is from the beginning of the company formation to the end of the calendar year, approximately from June through December, on the average.

20. By “infant” we mean a child born alive who is less than one year old at the time of departure from the staging area.

21. We multiplied the U.S. white population infant mortality by seven-twelfths of the annual mortality to account for the partial year that people were on the trail.

22. Ansley Coale and Melvin Zelnik, New Estimates of Fertility and Population in the United States (Princeton: Princeton University Press, 1963), 34, giving birth rates of 43 births per thousand persons per year for the U.S., 35 for England-Wales, and 31 for Sweden.

23. Haines, Estimated Life Tables for the United States, table 2, White Population, 1860.

24. These data correct earlier calculations of infant mortality rates reported to the media in, for example, “New Study: Mormon Pioneers Were Safer on Trek Than Previously Thought, Especially Infants,” Deseret News, July 20, 2014, at http://www.deseretnews.com/article/865607257/New-study-Mormon-pioneers-were-safer-on-trek-than-previously-thought-especially-infants.html?pg=all.

25. Brigham Young’s vanguard company left in April 1847 and had no deaths.

26. Patricia Rushton, “Cholera and Its Impact on Nineteenth-Century Mormon Migration,” BYU Studies 44, no. 2 (2005): 123–44.

BYU Pioneer Mortality Team

BYU Studies Publications