Why did the Atlantic Slave trade come into existence and How did it work commercially

Why did the Atlantic Slave trade come into existence and How did it work commercially?
The development that propelled much of the western world’s economy ahead between the 16th and 19th centuries was the creation of the Atlantic Slave Trade. To understand how it worked commercially, it is first necessary to look at how the Atlantic Slave trade came into existence in the first place, and further to that why Africa would become the nation of people that would feed the New world its slaves for four centuries. Put simply there was a need for a suitable source of slaves to work the land in the New World. Africa was chosen as there was already a native system in place that aspiring foreign nations took advantage of.
Although no one country can bear full responsibility for the creation of the Atlantic Slave trade, it was Portugal and Spain who first established trading links with West Africa. The ambitious traders found an existing slave system which they turned to their advantage. It was necessary to go looking elsewhere for slaves as the Native Americans had been wiped out due to disease and famine and Europeans were not able to cope with the harsh climate and working conditions. The Europeans found Africa to be a good source of slaves due to their availability and productivity, as well as suitability to the climate and task of working the plantations. Each slaving European nation established contacts with slave traders within Africa and through these men, the Europeans were able to acquire the Africans. This saw the generation of the Atlantic Slave Trade, it was comprised of European nations transporting slaves from the West African Coast to European colonies in the Americas in exchange for weapons, gold, cotton and other items being grown in the plantations. Trading goods for slaves was the central element to the complex triangular trading system. Exact numbers are difficult to surmise given the lack of accurate record keeping but it estimated that throughout the four centuries that the Atlantic slave trade existed, over eleven million African slaves were moved and shipped through the trade triangle.
When Europeans arrived at the New World at the end of the 15th Century, the demand for cheap or free labour to ‘cultivate their plantations’ quickly outgrew the existing population. The indigenous people had been largely wiped out by disease and conflict and Europeans were found not suitable for the working conditions. As such, Europe’s demand for slaves grew and that meant the African suppliers increased their raids on villages and small towns to meet the supply needs. Olaudah Equiano wrote his story which was published in 1788. Olaudah’s book tells the story of how he and his sister were kidnapped from their home and then separated by the slavers. He tells of how it was Africans who kidnapped them, Africans who separated them, and Africans who sold them to the Europeans. He tells of the anguish of himself and others like him that are beaten, starved and then sold like an animals. Equiano’s story would not be unique.
While Spain and Portugal are responsible for initially establishing the slave trade, on the other hand Africans bear some of the responsibility themselves. Powerful African kingdoms such as the Kongo were not strangers to the slave trade, some had grown both the size and success of their society with native slaves (albeit better treated than those sent to the Americas) nevertheless, they cooperated with the Europeans to sell other Africans into slavery. It was the African middleman, come entrepreneur, who ran trade routes into the areas of Africa that were inaccessible to foreigners in order to provide the Europeans what they wanted. The vast majority of slaves were prisoners of war, criminals or domestic slaves and because the practices had existed for such a long time, they had no issues selling slaves to foreigners.