Since 1907 Leonhardi engaged in the lively anthropological scientific discussion with the publication of the first volume of the Arrernte - and Loritja tribes.
The contemporary discussion around 1900 was affected by a severe lack of acceptance towards the, according to the European view, newly discovered cultures of the Aborigines.
In contrast Leonhardi stood for a humanistic notion of anthropology in the tradition of Adolf Bastian and Rudolf Virchow.
Leonhardi managed to confirm his claim for acceptance of the Aborigine-Cultures mainly in collaboration with Carl Strehlow and with a preciser handling of sources as the one of his scientific opponents.
Although Leonhardi published on Australian topics throughout his life, he acted out of a comprehensive anthropological interest, and worked on cultures in Europe, North America and New-Guinea.
Amongst discussions in terms of content, a controversy about methodological issues of data provision, field-research and scientific handling of sources was provoked.
The journal Leonhardi initiated and edited, containing the writings of Strehlow, was discussed by Lucien Lévy-Bruhl (La Mythologie Primitive), Émile Durkheim (Les formes élémentaires de la vie religieuse), Elias Canetti (Masse und Macht), and others.