The general scientific concensus is that the Indians were killed by Old World disease. A more recent discovery is that they were killed to an even greater degree by a Hanta virus native to the Americas.
The English created quite a bit of nasty propaganda about the Spanish, French and others who went to the Americas and blamed them for every sort of crime, including many of their own. Do not be misled by the "English Filter".
"A more recent discovery is that they were killed to an even greater degree by a Hanta virus native to the Americas."
Quite a lengthy thread on this topic, on FR, in fact.
Look it up. "Enlightenment" indeed!