Were there any other “isolated”/“uncontacted” tribes still living traditionally in the US? Or were there other tribes that had been in contact with settlers/gov/pioneers who largely continued the traditional way of life until later on?
Ishi was not the last "Wild Indian". He was not the last Yahi. He wasn’t “discovered” in the sense of never having contacted white society before, and he did not emerge from a “wilderness”. Most Native Californians had been exposed to white culture long before 1911 when Ishi was "discovered". Ishi was no exception.
What would actually constitute a "Wild Indian" is unclear in a practical sense as a description of Ishi’s circumstances, and it is unclear in a theoretical sense as well. At what point of assimilation does a native cease to be wild and become civilized? To illustrate how difficult the concept of “Wild Indian” is, consider that in Golla’s (2003) analysis of Ishi’s lexicon he identified the significant presence of many Spanish words. Can you be wild and use the invaders words? In addition, local settlers reported that Ishi was a person that was known to them. Can you be wild and in regular contact with the settler community?
The Ishi discovery story is a piece of quasi-anthropological mythology that is directly descended from Euro-american narrations of the "last wild Indian and the noble savage" (Field 2005:86). It tells the sad story of a displaced native Yahi man that had lost his family and was found, emaciated and traumatized, in a community near Oroville, California. There, he was placed in a jail (for shelter) by local residents, who then contacted Alfred Kroeber of the University of California. With the express permission of the Bureau of Indian Affairs, Ishi was sent to San Francisco to the University Anthropological Museum. He lived there, as a living exhibit, for the next five years until he died of tuberculosis in 1916.
Ishi’s story became famous following publication of Theodora (wife of Alfred) Kroeber’s book, “Ishi in Two Worlds”, in 1961. It is a wildly popular account of Ishi’s life at and around the museum, but critics note that it glosses over the serious issues that attend Ishi’s treatment and history. You will not find considerations of genocide, tribal identity, or or power differentials in Theodora Kroeber’s book.
Ishi’s story has been the source of disputes among historians, anthropologists and Natives Americans since the 1960s. The first major dispute concerns whether his tenure at the museum constituted a violation of his human rights. The second concerns the treatment of Ishi’s remains following his death that is perhaps most well described in the Orrin Starn book that Field reviews. In short, Ishi, contrary to his wishes and against the direction of Kroeber, was autopsied following his death while Kroeber was away. Theodora reports about this and it is heart-wrenching. What she nor Kroeber nor any other anthropologist involved reported is that his brain was sent to the Smithsonian, and was only returned following investigative reporting and repatriation requests by Native Californians (the Pitt River Tribe, the Maidu, and others).
Bearing in mind that the degree of wildness is subjective and problematic, there certainly were natives that were living in traditional ways out of the way of settlers elsewhere in California in the 20th century. Most natives had been either killed or relocated by the end of the Indian Wars of the1860s, but there were individuals and small families scattered here and there in the Northwest that lived in relative isolation using traditional subsistence practices. Some of these people became very adept at evading contact.
Just to use a couple of examples, Sally Noble a Chimariko woman, recalled to John Peabody Harrington in 1921 that she witnessed starving Wintu natives that had come into a settler community in Trinity County, California in the early 20th century. She described them as wild, meaning not speaking English and not having had much contact with white settlers. Elsewhere, Harrington reports a James Chesbro (Cheeseboro, Chesborough) story about “Ma-wee-ma” a Tsnungwe man who lived in the wilderness (such that it was) and taught Chesbro how to snare deer and conduct dances in accordance with the old ways. He was said to not like to interact with white people and so traded with natives who acted as intermediaries with settlers.
So there were some that were roughly coeval with Ishi, but I know of none later than that in California or elsewhere. This is likely because by 1911 natives had been coerced onto reservations, enslaved, or because their subsistence base was so disrupted as to make isolation no longer feasible.
Review: Who Is This Really about Anyway? Ishi, Kroeber, and the Intertwining of California Indian and Anthropological Histories Reviewed Works: Ishi in Three Centuries by Karl Kroeber, Clifton Kroeber; Ishi's Brain: In Search of America's Last "Wild" Indian by Orin Starn Review by: Les W. Field. Journal of Anthropological Research Vol. 61, No. 1 (Spring, 2005), pp. 81-93
Review: [Untitled] Reviewed Work: Wild Men: Ishi and Kroeber in the Wilderness of Modern America by Douglas Cazaux Sackman Review by: Herbert S. Lewis Anthropological Quarterly Vol. 84, No. 1 (Winter 2011), pp. 265-271
Golla, Victor (2003). Ishi's Language. In: Ishi in Three Centuries (Karl Kroeber & Clifton Kroeber, editors), pp. 208–225. Lincoln: University of Nebraska Press.