This collection consists of two subgroups: Evelyn J. Cameron Subgroup, and Ewen S. Cameron Subgroup.

Evelyn J. Cameron's Papers consist primarily of diaries (1893-1928) that chronicled her daily life including books she read, chores, lists of letters written and received, local and national events, photographs taken, social activities, verbatim copies of special letters, and weather. The diaries also include innumerable tidbits of information that reveal the fabric of her life--the number of eggs gathered and chickens killed per month; notes on the amount of butter she churned; methods of skinning a coyote or breaking a horse; accounts of money made from her photos and garden produce; lists of supplies; and Evelyn's favorite poems and quotes. In addition to the diaries, this subgroup also contains letters (1903-1929, 1974) both to and from Evelyn Cameron. The letters, especially those written to her family, are particularly valuable because they provide more insight into Evelyn's personality, and are more detailed than the diary entries. Also included are legal documents (1916-1917) regarding land purchases; miscellany (1893-1928) including lists of books and ranch animals, Christmas and sympathy cards, and notebooks; and clippings (1893-1923) removed from the diaries.

Ewen Cameron's papers consist of incoming correspondence (1908-1914), and legal documents (1903-1914) primarily related to property ownership and water rights. Also included in this subgroup are typescript and handwritten copies of various articles written by Ewen Cameron concerning Montana wildlife (1898-1914).