Olive Oatman is the historical counterpart on which character Eva on AMC's Hell On Wheels is loosley based.
"In The Blue Tattoo: The Life of Olive Oatman, Mifflin's 2009 contribution to the subgenre of American historical studies known as the pioneer captivity narrative, she recounts the slaughter of Oatman's family by marauding Yavapai Indians near the Gila River in Arizona, Oatman's abduction, and her subsequent assimilation into Mohave tribal culture---so much so that she consented to the chin tattoo that was a traditional signifier of femininity, among the Mohave. Mifflin considers Oatman's transformation from Mormon pioneer girl into what the Victorians melodramatically called a "white savage," analyzing the significance of her years among the Mohave and ultimate return to white society in light of Victorian gender politics."
Lorenzo D. and Olive Ann Oatman, brother and sister, traveled with their family in 1850 across the Plains. While encamped on the Gila River,they were attacked by Indians who killed most of the family, left Lorenzo for dead, and took Olive and her sister Mary into captivity. Although Mary died in captivity, Olive was eventually ransomed and joined her brother in 1857.