So why was American slavery so brutal?
I don't know. I never really got a satisfactory answer on that.
The Muslim Arabs initiated the African Slave Trade circa 800 CE.
African tribes would sell/trade their slaves to the Muslim Arabs who either kept them, or transported them to India to sell/trade for Indian slaves and then African and Indian slaves were transported to Indonesia and Malaysia to sell/trade for indigenous peoples and then Africans, Indians and Indonesians were transported to southern Africa and sold there.
Lather, Rinse, Repeat.
If you remember Apartheid, there were three groups: Whites, Blacks and Coloreds. Isn't that redundant? Nope. The Coloreds were Indians and Australoid peoples from India, Indonesia and Malaysia.
Shari'a Law governed slavery for Muslims:
1) Slaves had to sleep under your own roof
2) Slaves had to be taught to read and write...because
3) Slaves had to be taught the Koran
4) A slave that converted to Islam had to be freed
Generally, if a slave converted to Islam, you would marry him off to one of your daughters and give him a tract of your land to farm or a piece of your business as a wedding gift.
One more thing...abusing a slave was punishable by death.
The last person executed under Shari'a Law for abusing a slave was an Albanian Muslim in 1873 just before the
Tanzimat Reforms that banned slavery.
Contrast that with American style slavery where slaves were treated like cattle or other animals, punished for learning how to read or write, were not taught the Bible, were not given any "out" and there was no punishment of slavery.
It says a lot about Islam and Christianity, and about the cultures of the two, although at that time religion and culture were inextricably intertwined.
Islam was the only form of slavery that offered an "out." It was Roman custom to free your slaves upon your death, and there was sort of an "out" if you were male and a Legion member.
For example, Minos was a Greek slave who joined a legion and rose to Primus, or third in command of the legion. When he retired after 20 years of service, he was granted Roman citizenship and freed as a slave, but instead of being given the traditional tract of acreage (usually 140-160 acres of land) he was given a charter by the Roman governor of Trier to found a colony at the confluence of several rivers between Kaiserslautern and Strausburg (France).
It was called Au de Minos. Later, when the German tribes came through the name changed to Minosauwen, then, much later, the Latin-speaking Germans we call the French changed it to Miesauen and then later it became what it is known now: Miesau.
The slavery practiced by North American indigenous tribes, African tribes and many other groups did not offer an "out."
The Muslims introduced slavery to Europeans more than 600 years later in Muslim Spain. The tribes in Spain were quite brutal and uncouth (read Muslim accounts often written by Jews in Spain).
Slavery spread from the Spanish tribes (the Iberians, Catalans, Valecians, Aragons etc) to Portugal, then France, then Britain. The Dutch, Germans, and Norse were not really big on slavery, and I don't know exactly why that was, either.
The Spanish, French and British brought slavery to North America.
I never really got a satisfactory explanation as to why the British, French and Spanish never used tribal groups as slaves.
Take the French. They have several settlements near Detroit, Michigan and the local tribes had practiced slavery long before European colonization. The slave wars between the tribes was so brutal it interfered with the French fur trade, so the French made all sides sit down and talk it out to put an end to slavery, which the tribes eventually did within a few decades.
If people here are free for the taking, then why import slaves? The best answer I got was that "Native Americans" were too uncivilized to train, they were likely to rebel, their tribes might conduct raids to free them, and they were on their home turf, so they knew the land and could travel freely if they escaped and it's unlikely you'd ever find them again.
As far as the brutal treatment, the best argument seems to be that Black slaves were viewed as the descendants of Ham, and therefore everyone had a god-given right to treat them like trash.