Slavery began when European merchants started the Triangular Trade. The Triangular Trade was trading between these three regions: America, the Caribbean, and Africa. The Triangular Trade started slavery because the Americans traded the Africans goods from England like cloth, cowrie shells, tobacco, and metal goods. America wanted the African Americans as slaves. The slaves had to sail on "Slave Ships" to get to the Americas. The slave ships were miserable to the slaves. For example, the ships were filthy, it was full of diseases. Also, in many cases Africans couldn't handle it anymore so they just committed suicide. The original slaves in the Americas were natives but the natives started getting ill and died, so the Americans hired the Africans to be the new slaves. Why were the slaves needed in the first place? Well, the white people didn't want to do their own work so they had slaves to do it for them with NO pay! It started off using prisoners, but since they saw the Africans they saw how "different" they were so kept them as slaves. The northerners were the total opposite of the south because the south liked not paying slaves for fun. The north hated that, they were more selfless and had almost no slaves. Slavery was increased by the invention of the cotton gin. In 1790, there were 657,000 slaves needed in the south, by 1810 there was 1.3 million slaves. The reason why the invention created the bigger need for slaves was because the cotton was produced much faster, but the south didn't want to do that work.
Slaves in America were treated so poorly. The slaves would worked up to 18 hours each day. There were no weekends. The slaves had to make their own food, the masters did not buy food for their slaves so they had to eat fatty meat and cornbread. They were given no beds except an uncomfortable blanket and the slaves barely slept. The slaves were punished by being beaten or with a leather whip, depending on what you did you could get 100 strokes with the leather whip! They also could hang or imprison them if they did some thing really bad. The slaves could not be educated because if they knew how to write, then they could write a letter to escape. Also, slaves could not legally get married and plantation owners did want the women to have kids so they could have more slaves. Some of the women's masters would rape the enslaved women. Slaves could also go to church, but only with their masters. The treatment of slaves was terrible. The plantation owners would execute, rape, beat, and whip a slave if they needed to. For example, slaves who tried to escape had severe punishment, they could be beaten terribly.
Finally in 1865 slavery was illegal.