We passed on the offer of a review copy of the new novel by Kathleen O'Neal Gear and Michael Gear, but they do seem to be a remarkable phenomenon. Together they have fifty novels in about 25 years, and almost all are set in pre-contact aboriginal North American. And they are both professional archaeologists, who run an archaeological consulting firm in Wyoming.They also raise bison.
The new series, in which The Dawn Country is the second, is set in the history of the Hodenosaunee (ie, the Five -- later Six -- Nations or "Iroquois'), but the Gears' archaeological fictions cover most parts of North America and range from the Ice-Age migrations out of Beringia to contact times.
More about the Gears and their work here.