When Alexander was exploring the rainforest of northern South America at the turn of the nineteenth-century, Wilhelm pursued intensive sociolinguistic-ethnographic fieldwork on Basque, a non-Indo-European isolate, in the Pyrenees of Spain. Basque would attest as an ergative-absolutive language comparatively rare in Europe, but quite common in the Americas. Research on a language without a philological tradition required linguistic and anthropological field research, including the learning of its grammar, its uses and contexts, plus accompanying sociocultural customs. Humboldt recognized Basque as “a living image of their way of thinking and feeling,” for which he drew on proverbs, poetry, music, and dances. Conversely, distinctive Basque society was intelligible solely through the Basque language as part of an integrated theory of language in culture and society. Although Humboldt never identified Basque as Native American, his journey to the Pyrenees then became his substitute for a voyage to the Americas in the mind of German Humboldtians.