Wundt's V & ouml;lkerpsychologie (VP) is an exceptional case in the history of psychology. Outlined in 1863 in the second volume of Vorlesungen & uuml;ber Menschen- und Thierseele (Lectures on the Human and Animal Soul), VP was finally published 37 years later in 10 volumes during the last 20 years of the author's life. The work was characterized by an ambitious program of multimethod and transdisciplinary research. This article explores the intellectual and contextual reasons for the early successes and failures of VP. We analyzed n = 264 articles published in the German press and n = 220 books, reviews, and articles published in scientific journals that explicitly cited the 10 volumes between 1900 and 1920. VP received considerable criticism from linguists and philologists, who claimed that its results were of little practical use for their research. The first volumes of VP were criticized for their abstract character and psychological indifferentism; on the other hand, positive reviews emphasized their attempt to systematize and give a philosophical order to the individual investigations of philology, linguistics, comparative history, religious studies, and so on. The normative-methodological role that VP tried to play in relation to the other historical sciences was significantly criticized, and this was a determining factor in its diminishing impact over time. Some of Wundt's hypotheses were philosophically at odds with the project of German cultural imperialism that was being developed at the time and with which most of his intellectual enemies agreed.