Mississippian Sites
The three major mounds at Etowah and the largest temple mound at Etowah. 
Spiro, Oklahoma
Etowah, Georgia
Moundville, Alabama
The Mississippian culture lasted from before 800 A.D. to after 1500 A.D.  The four major sites were in Illinois (Cahokia), Georgia (Etowah), Alabama (Moundville) and Oklahoma (Spiro).  Cahokia was the largest and most populous of the four major Mississippian sites.  Trading is documented between the sites which all coexisted at the same time.  Ultimately, all the major Mississippian sites were abandoned.  Each site may have had different reasons for declining.  Warfare, poor soil and water conservation, the little ice age, and my personal favorite: political turmoil.  Political turmoil may have been fostered by social inequality and inherited positions of power.  Could it be that the common man, after being offered safety and food, got tired of turning over his crops and building mounds that were not truly his?  Longing for freedom, he may have left and taken his chances in small settlements.
Lessons to be learned for all of us.
Etowah was occupied off and on between 1000 A.D. to 1550 A.D. 
Etowah's zenith was around 1300 A.D.  
Moundville was occupied between 1000 A.D. to 1450 A.D. 
There were 32 mounds grouped around a rectangular plaza. 
Spiro was occupied between 850 A.D. to 1450 A.D. 
Spiro had significant political and religious influence in it's region from 900 A.D. to 1350 A.D.
Craig Mound at Spiro.  Conjoined funeral mounds with over 600 burials.
The artifacts discovered there indicated great wealth and a large trade network (California to Florida).
Unique amongst the sites for it's lack of fortifications and less effort spent on mound construction. 
Instead of spending time and effort on war and religion, they concentrated on peace and prosperity. 
Click here for photos of Mississippian artifacts.
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