Åke Hultkrantz (1920-2006) was born in Kalmar, Sweden. He earned a doctorate in ethnology from University of Stockholm in 1946, followed by a second PhD in comparative religion in 1953. Between 1948 and 1990, he often conducted fieldwork and lived among Californian Native American tribes, the Arapaho, and the Shoshone who adopted him as a tribal member. He held many distinguished academic appointments, and was a visiting lecturer at universities across Europe and the United States. He authored some four hundred papers and twenty-five books, including standard works on Native American religions. His interest in afterlife-related subjects, shamanism, and peyote spanned his entire career.