At the height of that trade, over 10,000 Eastern Europeans were enslaved each year between 1500 and 1650 for export to North Africa, the Middle East, and South Asia … a total of 1.5 million…
Differences from the African Slave Trade
The white slave trade differed from its black counterpart in a few key ways. In Africa, a slave-trader typically purchased prisoners of war who had already lost their freedom through local conflicts. In Europe, he played a more active role.
This was the case with the Crimean Tatars who lived under Ottoman protection in the Black Sea region. Beginning in the mid-15th century, they would fan out each year on raids into what is now Ukraine and southern Russia. These raids served no military purpose, being driven by the profits to be made in the slave trade:
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The white slave trade was different in a second way. Most black slaves were destined for physical labor on plantations. There was thus a stronger preference for men over women. In contrast, white slaves were used more for domestic service, particularly concubinage and marriage. There was thus a stronger preference for women, as reflected in the sex ratio of the slave population: black slaves were predominantly male, and white slaves predominantly female. Furthermore, while blacks of both sexes sold for the same price, Russian and Circassian women fetched 50% more than men of the same nationality. (Verlinden, 1977, pp. 211, 224, 306, 315, 330-331, 460, 517; see also Frost, 1990). This price differential continued until the end of white slavery. A mid-19th century report from Turkey states that a “trained, strong, black slave” would cost 4,000 to 5,000 piasters, whereas “white slave girls of special beauty” were worth 50,000 piasters or more (Lewis, 1990, p. 13). ..
Conclusion
Slave trading existed in many parts of the world and during many historical periods. Trading in fair-skinned women, however, was much more limited in space and time. There is no evidence of it during Roman times, at least not on a large scale. If a Roman notable wanted a bride with milk-white skin, he would look among the families in his entourage and not among the slaves at the local market. After all, a native-born woman of good family would bring a dowry and valuable family connections.
All of this changed in the 7th century with the dramatic expansion of the Arab world into the Middle East and thence into North Africa and Spain. The new elites were darker in skin tone and, also, more polygynous. It was these two factors that would fuel demand for fair-skinned brides and concubines.
A third factor was of course the relative weakness of European societies, particularly during the Dark Ages that followed the collapse of the Roman Empire. With the gradual strengthening of European states, this trade increasingly took the form of hit-and-run raids that focused on poorly defended areas, such as the plains north of the Black Sea. This raiding would finally end only with European annexation of those “states” that earned most of their income from the slave trade, such as the Khanate of the Crimea and the Beyliks of North Africa.