The Pope.

In the early 1400s the Portuguese were becoming accomplished sailors. They would spend the first half of the century exploring for trade routes and colonizing a few Atlantic Islands. By 1453 and the fall of Constantinople their trade in spices was greatly limited and by 1488 they would unlock passage to India by going around Africa.

One such trader, Antao Goncalves, came up with a new plan in 1441. After completing the trade he set out to do, he grabbed a couple people and stole them as slaves. Upon returning this was seen as a smart move so the practice began to grow. About a decade later there were serious questions around it, so Pope Nicolas V clarified things in a series of Bulls, one such authorizing the Portuguese King;

...to invade, search out, capture, vanquish, and subdue all Saracens and pagans whatsoever …[and] to reduce their persons to perpetual slavery, and to apply and appropriate to himself and his successors the kingdoms, dukedoms, counties, principalities, dominions, possessions, and goods, and to convert them to his and their use and profit

Africans were fair game as slaves from then on (slaves in Europe had commonly been brought by Turks or moors already, this removed the middle man).

Fast forward almost 200 years to Jamestown and there were indentured servants. One named John Punch tried to run away around 1640. As punishment his indenture was made permanent. In the mid 1650s another man, John Casor, allegeded he fulfilled his indenture. His master disagreed saying he owned the man and not the indenture contract. The court sided with the owner, changing the status of Casor from indentured to slave. The door soon opened and the cheap source of labor going from Africans committing tribal raids to Portuguese colonies buying these slaves to the Caribbean/S. America plantations using them in place for 100 years already then became a vital resource to American growth.

We are now teaching children about the origin of slavery. You know, that America started it in 1619 when Portuguese owned slaves were intercepted and brought by the British to Virginia then treated as indentured servants (it wasn't until 1641 that the first slave laws would exist in the colonies, 1661 for Virginia). It's called Project 1619 and numerous historians have already spoken against the lack of historical accuracy presented.

Hi there! You’ve asked a question along the lines of ‘why didn’t I learn about X’. We’re happy to let this question stand, but there are a variety of reasons why you may find it hard to get a good answer to this question on /r/AskHistorians.

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