Europeans who came to the New World were seeking for E: wealth.
Christopher Columbus was looking for a new trade-route with India and China when he came across a new continent full of resources.
The riches of America allowed all Europe to grow. New agricultural products were imported to Europe, such as tomato, corn, potatoes or cocoa, as well as silver and gold. These products had a great impact on the European economy and encouraged the growth of capitalism.
Ever since, everyone that came to "The Americas" was looking for economic resources. This is why several colonies were founded after the conquest of the Aztecs, Incas, and other large Native American populations: to exploit both natural and human resources.