It is pretty secular, maybe a humanistic bent if any at all. One story, I recall, tells about the Hopi rebellion against the Catholics and is clearly cheering for the Hopi.
Each story stands alone from the next, is illustrated with peaceful and engaging color sketches, and takes a page or three and fifteen to twenty minutes to read. It is an excellent supplement. I wish she had been more careful about including all of the most commonly told stories, so that we could use it as a spine.