Death on the Trail
The trek to California was one of known dangers and peril. Travellers understood the difficulty with which they would reach what many of them referred to as the "promised land," which served as part of the experience of "seeing the elephant." However, the difficulties that they prepared for were often not the difficulties that they faced in reality. Many, such as William Murray, anticipated antagonistic encounters with Native Americans. This fear proved unnecessary for Murray, though it was not altogether ungrounded. There were in-fact some cases of Native Americans killing Gold Rush travellers, such as is relayed by the Alta California newspaper on 28 August 1849, when it says, "[Francis Pickenig died] at Feather River Meadows, of wounds received in an engagement with the Indians."
However, as can be recognized through the diaries of Amos Bargdoll and William Murray, the greatest killer on the trail for the travellers was illness.
Bargdoll details only one day after having left Fort Kearney on his trek that "a man from Ohio died of Cholera" one mile from their camp. One of the more sad aspects of Bargdoll's diary is the detailed deterioration of one of Bargdoll's colleagues, Kent. On Saturday, June 8th, Bargdoll details that one in his camp, Uriah Pruet was "very sick." Two days later, a man named Kent who was friends with Pruet began complaining of feeling bad (this notably after passing three graves on the trail). On Wednesday, June 12th, Bargdoll writes, "Kent taken suddenly very ill." After several days of "Kent being too unwell to travel," he notes on June 16th that "Kent got worse in the evening. We encamped and he still continued to sink and died about 9 oclock in the evening. He did without a struggle. This occurrence cast a deep overloom over our little company. We buried him near the root of a large cottonwood near the southside and carved his name, residence, and age upon the board at the head of his grave." They were forced to move on the next morning "after interring the corpse."
Unfortunately, this was not the end of the notations on death in Bargdoll's diary. On June 21st he notes that his party passed three fresh graves of some who had died the day before. On July 10th he notes a group of men burying a man "who died of Cholera yesterday." Having finally arrived in California, death was still a present threat, as Albert Hancock (a hometown friend of Bargdoll's) died of "apoplexy" (stroke) on September 5th.
This experience is nearly mirrored by Murray, as he and his company had no more than left Missouri that "McCoy" died "and was buried on the prairie." Again he pens on August 24th that W.C. Maxwell died in the evening, being buried on the banks of a little creek in the Hot Spring Valley.
Neither of these journals describe any difficulties arising between the travellers and Native Americans, and the primary source materials indicate that this was not unique. For example, The Missouri Republican published on 11 October 1850 that there were 14 reported deaths at Fort Laramie that summer, 11 of which died of cholera, the other three having no noted cause of death.
For further reading, see John E. Baur's "The Health Factor in the Gold Rush Era," in Pacific Historical Review 18, No.1 (Feb. 1949), pp. 97-108.
 Death on the Plains: Notations by Travelers to the West along the Overland Trail, transcribed by S. Cook. http://genealogytrails.com/
 William Murray Diary, Tuesday May 22.
 Mary Harrell-Sesniak. "Stories Told by California Gold Rush Obituaries," Geneologybank. 22 March 2016. https://blog.genealogybank.com/
 Amos Bargdoll Diary, 31 May 1850 - 16 June 1850.
 William Murray Diary, Foreword.
 Ibid., Friday August 24.
 "List of Illinois Deaths Reported at Fort Laramie," Missouri Republican. 11 October 1850.