This book about the Donner party.
“Drawing on fresh archaeological evidence, recent research on topics ranging from survival rates to snowfall totals, and heartbreaking letters and diaries made public by descendants a century-and-a-half after the tragedy, Ethan Rarick offers an intimate portrait of the Donner party and their unimaginable ordeal.”
https://www.amazon.com/Desperate-Passage-Donner-Perilous-Journey/dp/0195383311