The first part begins with the history of California before European colonization , and describes the territory of the Yana people , within which the Yahi inhabited the southern region . Kroeber suggests that the Yahi were never numerous , and probably never numbered over 3,000 . She writes that though they once occupied a large section of the Sacramento Valley , they were likely pushed into the hills by invasions of other , more numerous , Native American peoples . The first section also describes the Yahi language , and the landscape of their territory near Mount Lassen . Multiple chapters in the first section focus on the destruction of the Yahi by white settlers . The Yahi territory began to be affected when the Mexican government of Alta California made land grants to settlers in the Yahi lands in the 1840s : most of these grants were later confirmed by the US government . The California Gold Rush began soon afterward , bringing huge numbers of settlers into the region . Fierce military conflicts followed , leading to the destruction of the local Native American peoples over the next few decades , until eventually only a small band were left to found the settlement where settlers encountered them in 1908
destruction of the local Native American peoples
California Genocide
Ishi in Two Worlds