Final answer:
The Islamic Slave Trade began before the spread of Islam and involved the trading of millions of slaves from Africa and Europe. Slaves performed tasks such as building fortifications and serving as enslaved galley people.
Step-by-step explanation:
The Islamic Slave Trade portion of the African Slave Trade began long before the spread of Islam across North Africa. Arab slave trading, which exchanged enslaved people for goods from the Mediterranean, existed prior to the rise of Islam. Many of the slaves in the Islamic Slave Trade performed various tasks such as building coastal fortifications and serving as enslaved galley people. Women were often added to the harem. It is difficult to determine the exact number of slaves traded in this way, but it is estimated that millions of African and European slaves were traded in the Islamic Slave Trade.