Heirloom. Native American native squash. A tribal landrace of mixed small, finely flavoured, disease resistant pumpkins.
The variety originated when three Indian tribes, the Hidatsa, Arikara and Mandan, were living in close proximity for protection, near the confluence of the Missouri and Knife Rivers. 1
Knife River, Hidatsa, Mandan
1 http://rareseeds.com/knife-river-squash.html