With exploration arising in the 1400 s, so did the completion for success between Portugal and Spain. Both countries were in search for the ultimate prize of exploration, gold. Portugal sought after Africa and Spain attempted to find more in the Americas. Even though the African slave trade seemed racist in historical perspective, it was indeed more for economic benefits instead because of the necessity of workers by Spaniards and fact that slavery was accepted in Africa.
The necessity of workers by Spaniards in the Americas was a reason why African slave trade was based more on necessity rather than racism. They were in need of cheap workers to work the mines to extract the gold form the Americas to transport back to the motherland. Portugal got involved with this because they saw an opportunity to get these slaves to trade with Spain in return for goods that they desired. In summary, the slaves were not seen by their skin color or ethnic background, but as an opportunity for economic enrichment.
A key point of the slave trade was that African nations were willing to participate in the trade. The African states of Dahomey and Oyo sent masses of slaves each year to be sold along the Slave Coast. Dahomey sent about 20,000 slaves per year alone. Another nation that was an active participant was the Kongo Empire. They supplied the Portuguese with slaves that they needed for their sugar plantations, and Nzinga Mbemba even converted his empire to Christianity and his name to Afonso I. In summary, the slave trade was not a racist issue, but that of economic necessity.
In conclusion, the African slave trade was more of economic necessity rather than racism as seen from the need of the Spanish in the Americas and from the participation of African nations. African slaves were not seen as blacks but as a highly demanded mean of trade. The slave trade was the beginning of whole new era that benefited the each nation involved in the trade of the Atlantic Ocean.