Deutsche Mythologie

Deutsche Mythologie is Jacob Grimm's own 1835 philological study, and it is the source of the reconstructed Continental goddess Ostara, whom Grimm inferred from the Old High German name for Easter, Ostarun, read alongside Bede's single eighth century mention of an Anglo-Saxon goddess Eostre. As the originating text it is the correct source for how that reconstruction was actually built and on what evidence. Its limit is exactly that: it is a nineteenth century philological inference from a place-name pattern and one outside testimony, not a report of an attested cult, so a claim asserting Ostara as a documented, worshipped goddess rather than a scholarly reconstruction needs to be checked against the thin primary evidence Grimm himself was working from.