The Mississippi Civilization.
This brilliant, highly developed—at least for its time and background—and urbanized civilization flourished between 800 and 1600 AD east of the Mississippi River in what are now the states of Missouri, Mississippi, Tennessee, and Illinois.
I would even go so far as to call them the "Mesopotamians of America."
Let me explain this in more detail.
1. Their way of life was almost exclusively urban.
Everything revolved around a life-giving river: the Mississippi.
They lived in and around huge urban centers, which were mainly oriented around ceremonial squares and temples.
Cahokia, the largest city discovered, was, for example, a huge center surrounded by small towns and villages - the suburbs.
The image below shows the city in question:
pyramid-shaped temples, the largest of which stood at the center of a central square, and small houses arranged around local squares.
Outside the city walls were other villages and towns, forming a suburb.
Cahokia was the largest city in North America around the year 1600 and was not surpassed until 180 years later by Philadelphia (with 40,000 inhabitants).
2. Their culture was conceived as a hierarchical system and oriented towards shared beliefs and values.
It appears that the Mississippians had a fixed clergy:
priests, executioners, and, of course, a large number of followers.
It is believed that the Mississippians (like their Nahua neighbors in Mexico) were involved in large-scale human sacrifices,
using beheading or strangulation.
From a sociological perspective, Mississippians constituted a civilization, as their society consisted of an institutionalized hierarchy and a complex chieftain system.
Furthermore, the dominant urban center (e.g., Cahokia) held a certain position of authority over its satellite settlements.
Finally, Mississippians were avid farmers whose lifestyle revolved around corn cultivation.
3. Finally, their civilization was prosperous enough to develop fine arts and pottery.
Mississippians were not only successful farmers, urban planners, and a highly organized society, but also artists.
Their artwork still reflects the uniqueness of their civilization today.
Finally, this wonderful civilization vanished for unknown reasons shortly before the Europeans arrived.
Frankly, that coincidence is pretty cool, to be honest.
To put it simply:
The Mississippians were a highly developed culture.
They were possibly the most advanced civilization in the pre-Columbian United States.
In any case, they were the most mysterious and least known civilization on the American continent.