What ultimately happened to the estimated 10 million indians living in north america at the time of columbus' arrival?

  Big portion of the estimated 10 million Indians of North America at the time of Columbus's arrival died in the period that followed. That was mainly due to two factors:

1. Battles; there were lots of battles between the Indians and the European settlers in which the Europeans had the advantage of better weapons and most of the time the Indians were the ones with much more casualties.

2. Diseases; most of the deaths in the Indian populations were actually caused by diseases because the European settlers brought with them lots of new diseases to which the immune system of the Indians was not used to and had no defence, so even some diseases that among the Europeans are considered as minor and not dangerous, among the Indians turned out to be fatal.

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