Why did Europeans and Englishmen change their views of American Indians from positive to negative?
Some European nations never had positive opinions regarding the
Native People of North America while some started out with very cordial relations which quickly devovled.
Spain saw the native peoples as savages that needed to be saved or as sources of expendable labor. They saw the deaths of the natives from diseases as signs from God that they were evil and that Spain was destine to rule over the lands they possesed.
France saw the economic sense of keeping good relations with the natives and they strove to make those relationships stronger. French fur trappers lived with the tribes, married into them, visited often, and brought gifts when they could. These strong bonds paid off later on when conflicts broke out between France and her colonial neighbors.
England had a very hot/cold relationship with the natives. At first they maintained good relations because of the power imbalance that existed. In places like Plymouth the Pilgrims came to depend on the native peoples for food, supplies, and medicines. They invited them over for feasts and participated in raids against enemy tribes to maintain good relations. In Jamestown, they tried to maintain good relations because of the strength of the local tribes.
These arrangements quickly fell through in most cases. This was in large part due to land deals that were percieved as corrupt by the natives. This led to conflict, and eventual war with most English settlements where the natives enjoyed early success and eventually lost due to the force of numbers on the English side. Tales of native cruelty in war helped turn the English midset against the natives despite their long-standing alliances in some regions.