Expanding European empires in the New World lacked one major resource -- a work force. In most cases the indigenous peoples had proved unreliable (most of them were dying from diseases brought over from Europe), and Europeans were unsuited to the climate and suffered under tropical diseases. Africans, on the other hand, were excellent workers: they often had experience of agriculture and keeping cattle, they were used to a tropical climate, resistant to tropical diseases, and they could be "worked very hard" on plantations or in mines.
Was Slavery New to Africa?
Africans had been traded as slaves for centuries -- reaching Europe via the Islamic-run, trans-Saharan, trade routes. Slaves obtained from the Muslim dominated North African coast however proved to be too well educated to be trusted and had a tendency to rebellion.
See The Role of Islam in African Slavery for more about Slavery in Africa before the Trans-Atlantic Trade began.
Slavery was also a traditional part of African society -- various states and kingdoms in Africa operated one or more of the following: chattel slavery, debt bondage, forced labor, and serfdom. See Types of Slavery in Africa for more on this topic.
What was the Triangular Trade?
[pic]Image: © Alistair Boddy-Evans. Licensed to About.com, Inc. All three stages of the Triangular Trade (named for the rough shape it makes on a map) proved lucrative for merchants.
The first stage of the Triangular Trade involved taking manufactured goods...