Skipping ahead two turns, Inuit found Qausuittuq in the Aleutians, effectively cutting off Blackfoot's two island colonies until open borders or deep-sea travel; i don't see any evidence of open borders between the anti-Sioux allies. Too soon?
The generally-demilitarized nature of this area bodes well for peace between the two. Meanwhile, A Mexican scout noses around in habitable, claimable space in the Inuit hinterland. What could go wrong?