Religion / Missionary Effort converting the people of the world to either Catholic or Protestant Christianity
Profit / Greed - desire to make money
Expansion of Power - expanding the power of the state by having larger colonial empires than their rivals
European racial attitudes (attitudes of superiority) - they felt like it was their duty to civilize other peoples
the search for raw materials to feed industry (from the Industrial Revolution) - metals, coal, etc. instead of gold
searching for markets to export - the markets have the resources and also are the markets
