Wilhelm von Humboldt (1767–1835), an early pioneer in the philosophy of language, linguistic and educational theory, was not only one of the first European linguists to identify human language as a rule-governed system – the foundational premise of Noam Chomsky's generative theory – or to reflect on cognition in studying language; he was also a major scholar of indigenous American languages. However, with his famous naturalist brother Alexander 'stealing the show,' Humboldt's contributions to linguistics and anthropology have remained understudied in English until today. Drechsel's unique book addresses this gap by uncovering and examining Humboldt's influences on diverse issues in nineteenth-century American linguistics, from Peter S. Duponceau to the early Boasians, including Edward Sapir. This study shows how Humboldt's ideas have shaped the field in multiple ways. Shining a light on one of the early innovators of linguistics, it is essential reading for anyone interested in the history of the field.