David Edwin Folsom was born in 1839 in Epping, New Hampshire. He began training as an engineer but went west to improve his heath on the advice of a physician. A member of the July, 1862 Fisk expedition from Minnesota, Folsom arrived in Bannack before the years end to take up mining. From there he moved to Virginia City, Willow Creek, and Confederate Gulch where he was working with this friend Charles W. Cook by 1869. In 1875 Folsom returned to New Hampshire where he married Lucy Jones in 1880. The couple returned to Montana where they operated a ranch near the Smith River. Folsom held several political positions in Montana including Meagher County Treasurer, state senator from Meagher County, member of the Montana Capitol Commission, and he unsuccessfully ran for governor as the Republican candidate in 1900. About 1903, the Folsoms moved to California where their son, David M. Folsom, was on the faculty of Stanford University. David E. Folsom died at his home in Palo Alto on May 18, 1918.

In September 1869, Folsom joined with Charles W. Cook and William Peterson to explore the country which would become Yellowstone National Park. Starting from Diamond City on September 6, 1869 and traveled to Gallatin County, following Trail Creek to the Yellowstone River which they followed up to Tower Falls. From that point they went up the Lamar Valley before turning west to again meet the Yellowstone at the head of the Grand Canyon. Their route took them around the north shore of Yellowstone Lake, through the Upper and Lower Geyser Basins, and down the Madison River. They arrived back in Diamond City on October 11, 1869.

From the field notes they kept during the trip, Folsom and Cook collaborated on a manuscript "journal" to describe the Yellowstone Country. An edited copy given to a writer named Clark eventually resulted in its publication in the in July 1870, crediting only Cook as the author. The article was reprinted and credited to Folsom by Nathaniel P. Langford in 1894. Around the turn of the twentieth century both Folsom and Cook were contacted by Montana Agricultural College professor Victor K. Chesnut who wanted to republish their complete original composition, but after borrowing Cook's copy of the original Chesnut likely left the document in the chemistry building which burned in 1916. Folsom retained his copy of the manuscript composition which became the property of his great grandson, David A. Folsom, the donor of this collection. The transcription, letters, and notes of Chesnut have been accessioned as Collection 1268