As a part of my research for a couple "local history' writing projects, I've begun reading a relatively new book called Murder State: California's Native American Genocide, 1846-1873, which is about how Native Americans in California experienced horrible genocide in the early days of California statehood. This is a fact not many Californians are aware of. It has, for many years, been a kind of "silenced history." In the introduction to his book, scholar Brendan C. Lindsay gives a brief overview of some books which have been written on this topic, which I include here to show that this is a real thing, and a topic which I plan on researching more.
1.) The Destruction of California Indians by Robert Heizer (1974)
2.) Genocide in Northwestern California: When Our Worlds Cried by Jack Norton (1979)
3.) Genocide and Vendetta: The Round Valley Wars of Northern California by Lynwood Carranco and Estle Beard (1981)
4.) Killing for Land in Early California: Indian Blood at Round Valley 1856-1863 by Frank H. Baumgardner III (2005)
5.) Indian Survival on the California Frontier by Albert L. Hurtado (1988)
6.) Exterminate Them! Written Accounts of the Murder, Rape, and Enslavement of Native Americans during the California Gold Rush edited by Clifford Trafzer and Joel Hyer (1999)
7.) Murder State: California's Native American Genocide, 1846-1873 by Brendan C. Lindsay (2012)
There are, or course, other works that have been written on this important topic, but there remains much more research to be done in the field of California Native American genocide studies.