The aboriginal population of Canada during the late 15th century is estimated to have been between 500,000 and two million. Repeated outbreaks of Old World infectious diseases such as influenza, measles and smallpox (to which they had no natural immunity) were the main cause of depopulation. This combined with other factors such as dispossession from European/Canadian settlements and numerous violent conflicts resulted in a forty- to eighty-percent aboriginal population decrease after contact. For example, during the late 1630s, smallpox killed over half of the Wyandot (Huron), who controlled most of the early North American fur trade in what became Canada. They were reduced to fewer than 10,000 people.