If slavery almost died out in the Middle Ages, what brought it back? What were some of the similarities and differences between slavery in Africa and European slavery?

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Slavery became increasingly uncommon through the Middle Ages replaced by serfdom by the 10th century, but began to revive again towards the end of the Middle Ages and in the Early Modern Era. The Byzantine–Ottoman wars (1265–1479) and the Ottoman wars in Europe (14th to 20th centuries) resulted in the capture of large numbers of Christian slaves. The Dutch, French, Spanish, Portuguese, British and a number of West African kingdoms played a prominent role in the Atlantic slave trade, especially after 1600.

Explanation:

the correct answer is d) written language.