My e-version contained a considerable number of errors, and the translation may have contributed to that.
Nevertheless, Gronbech produced a foundational piece of work in these two volumes. He challenged pre- and misconceptions about the Northmen, but also provided profound and inspiring ideals with which to construct alternate, non-dualistic worldviews. No doubt much of the literature of the northern pagan movement has borrowed from this source.
My version was over 10,000 pages long, so I won't try to review the specific content, except to mention one aspect I felt was a failing. Toward the end of the second volume, he attempted to rationalize the myths by portraying them as images of real-world pagan rituals. Considering the scholarly depth of the bulk of the work, it was a little odd from my modern viewpoint, but easily forgiven. After all, he was publishing just as Carl Jung was first revealing his methods to the world and was probably not yet familiar with archetypes. Had Gronbech the benefit of a Joseph Campbell, no doubt the final chapters of "Culture of the Teutons" would have read very differently.
I will suggest that a first-time explorer into the northern mind wait before diving into this ocean. Read a lot of sagas and all the Eddas first.