Establishing colonies has been known since ancient times (for example, the Greeks had colonies in many regions of the Mediterranean), but it was in the Age of Discovery when large-scale colonisation truly begun. Around the 15th century, various European powers began colonising distant lands, establishing settlement in the Americas, Africa, Asia, and pretty much every other piece of land that hasn't yet been claimed by the competition. Colonialism was mainly profit-driven, but there were also other factors like scientific exploration, political struggle, or evangelization. For nearly half a millennium, the colonialism was the decisive element in global politics; it was in the 20th century when the system fell, and the world changed again.