Thank you for sending your question.
It is great that you are seeking answers in such an honest and humble way. May Allah (The One & Only God & Creator of the Heavens and the Earth and everything therein) guide you to the Truth and what’s best in this life and the next.
Islam & Slavery
Islam never encouraged slavery. Islam came while slavery was already well established worldwide. So, Islam encouraged the freeing of slaves and regarded it as a highly virtuous act that leads to Paradise and expiating one’s sins.
For example, Ibn ‘Umar said, “I heard the Prophet, may Allah bless him and grant him peace, say,
‘The expiation for someone who slaps his slave or beats him more than he deserves is to set him free.'” [Al-Adab Al-Mufrad]
Islam also encouraged freeing and marrying slaves legally and giving them full rights.
It was narrated from Abu Musa that the Messenger of Allah said:
‘Whoever has a slave woman and teaches her good manners and educates her, then sets her free and marries her, will have two rewards. [sunan ibn majah]
Regarding captives, Islam did not start, promote or encourage taking war captives. Rather, if Muslims were fighting armies that do not take captives, then their captives with the Muslims do not become slaves. And vice versa. The other options available for captives are to pay a ransom and get free or get exchanged for Muslim captives.
Additionally, Islam ordered masters to feed and clothe slaves from what they eat and wear, or else they will be at fault.
Narrated Al-Ma’rur, at Ar-Rabadha I met Abu Dhar who was wearing a cloak, and his slave too was wearing a similar one. I asked about the reason for it. He replied, “I abused a person by calling his mother with bad names.” The Prophet said to me, ‘O Abu Dhar! Did you abuse him by calling his mother with bad names; you still have some characteristics of ignorance. Your slaves are your brothers and Allah has put them under your command. So whoever has a brother under his command should feed him of what he eats and dress him of what he wears. Do not ask them (slaves) to do things beyond their capacity (power) and if you do so, then help them.’ ” [Sahih Al Bukhari]
So, the truth to the matter is that the Islamic teachings equated between masters and slaves, forbade pride and arrogance, closed doors for the growth of slavery and opened numerous doors for freeing slaves gradually and organically in the society.
Allah Honored All Mankind. No Race Has Inherent Superiority
You must know that to Allah, we are all equally His creations and slaves.
Allah Almighty says in the Quran
“O mankind, indeed We have created you from male and female and made you peoples and tribes that you may know one another. Indeed, the most noble of you in the sight of Allah is the most righteous of you. Indeed, Allah is Knowing and Acquainted.” (Quran 49: 13)
And The Prophet (peace be upon him) said:
“Allah, Most High, has removed from you the pride of the pre-Islamic period and its boasting in ancestors. One is only a pious believer or a miserable sinner. You are sons of Adam, and Adam came from dust. Let the people cease to boast about their ancestors.” [Sunan Abi Dawud]
Moreover, the Messenger of Allah said:
“[…] Verily there is no superiority of an Arab over a non-Arab or of a non-Arab over an Arab, or of a red man over a black man, or of a black man over a red man, except in terms of taqwa (piety/God-Consciousness). Have I conveyed the message?” They said: The Messenger of Allah (blessings and peace of Allah be upon him) has conveyed the message. [Classed as Sound by al-Albaani]
Accordingly, the trade you’ve mentioned is a corrupt business practiced by some people from the East and the West. These people are dissociated from Allah, The Most Merciful who honoured all His creation.
These people are not following Allah, they’re following the evil of their own souls. Do not mistake that with Islam.
And Allah knows best.
I hope this helps.
Salam and please keep in touch.
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