Answer:
This is true as the Natives were not immune too many diseases that the Europeans brought, among which the most fatal one were smallpox.
Step-by-step explanation:
Many historians are arguing that what Europeans couldn't do with weapons and fire they did with diseases they brought. Entire villages and tribes were erased from the face of the Earth by this invisible threat.
Of course, it is hard to find precise data on this, but we can conclude that the answer is true without a doubt.