Final answer:
The new resource introduced to the American Indians through Hernando de Soto’s expedition was European diseases, which had devastating effects on native populations.
Step-by-step explanation:
Throughout Hernando de Soto's expedition from 1539 to 1542, a new resource was forcibly introduced to the American Indians that had a profound and lasting impact. This new resource was not material wealth in the form of gold or silver as many conquistadores sought, but rather a more insidious and unplanned import: European diseases. These diseases, to which the native populations had no immunity, spread rapidly and led to severe depopulation and disruption of indigenous communities. De Soto's journey, covering areas such as today's southeastern U.S., introduced this new resource inadvertently as the expedition members interacted with various Native American tribes.
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