Fresh off an ice age there was soon to be civilization, including slavery, wars, atrocities, and more wars, but as far as political entities were concerned, these late-comers in raising a continent can point to profound advancements in multi-national trade and relations, and multi-lingual written language (lost), and remarkable trans-generational management of resources fostered and cultivated in the temperate rainforest of these Coastal Nations.
It is the history of the Coastal Indigenous people of North America which informs about the direction the world of nature is taking with climate. It wasn't Indigenous people causing ice to recede enough to allow formation of human settlements in coastal areas starting 6,000 years ago, when vast human developments were well underway south of these areas.