How many Native Americans died from smallpox?

As it is true it's more than millions. In the 18th century alone, 400,000 Europeans died each year. in the 20th century, the WHO (World Health Organization) estimated about 300-500 million deaths. Many more people have died, as this has dated back to 10,000 B.C.

As late as the 18th century, smallpox killed every 10th child born in Sweden and France. During the same century, every 7th child born in Russia died from smallpox.