Many archaeologists and anthropologists believe that the League was formed about 1450 .
Reliable sources link the origins of the Iroquois confederacy to 1142 and an agricultural shift when corn was adopted as a staple crop .
Many archaeologists and anthropologists believe that the Iroquois confederacy was formed about 1450 .
Reliable sources link the origins of the Iroquois confederacy to 1142 and an agricultural shift when corn was adopted as a staple crop .