Answer:
Slavery is actually a very ancient phenomenon, as old as civilization itself. All the Ancient civilizations like Sumer or Egypt practiced slavery, usually by conquering weaker peoples and taking prisoners of war as slaves.
In the Americas, slavery started almost immediately after the Portuguese and the Spaniards arrived in the continent. They formed colonies in the Caribbean and Brazil, and imported African slaves to work in large plantations, mostly of sugar.
In the United States, large-scale slavery also started when the south began to be colonized, and the warmer and humid climate allowed for the cultivation of cash crops like tobacco, rice, sugar, indigo, and specially, cotton.
