Since al-Andalus was a situated in the religious border zone, it had the conditions necessary to become a center of slave trade between Christian and Pagan Europe and the Muslim Middle East.
Slavery existed in Muslim al-Andalus as well as in the Christian kingdoms, and both sides of the religious border followed the custom of not enslaving people of their own religion.
Due to manumission being a form of piety under Islamic law, slavery in Muslim Spain couldn't maintain the same level of auto-reproduction as societies with older slave populations.
[7] Forming relations between the Umayyads, Khārijites and 'Abbāsids, the flow of trafficked people from the main routes of the Sahara towards Al-Andalus[8] served as a highly lucrative trade configuration.
The archaeological evidence of human trafficking and proliferation of early trade in this case follows numismatics and materiality of text.
[11] This major change in the form of numismatics serves as a paradigm shift from the previous Visigothic economic arrangement.
Additionally, it demonstrates profound change from one regional entity to another, the direct transfer of people and pure coinage from one religiously similar semi-autonomous province to another.
The Almohads broke Islamic law by taking Muslim women and children as slaves during the conquest of the Almoravid Emirate in the 12th-century.
[13] When Tlemcen was taken by the Almohad army, Ibn al-Athir stated that "The children and womenfolk were taken as captives.... Those who were not slain were sold at minimal prices".
The women were sold and everything [all the booty of the conquest] went back to the treasury", and Ibn Sahib al-Sala that "[Abd al-Mu'min] distribyted the houses [of the Marrakhsis] to [the Almohads].
Periodic raiding expeditions were sent from Al-Andalus to ravage the Christian Iberian kingdoms, bringing back booty and people.
For example, in a raid on Lisbon in 1189 the Almohad caliph Yaqub al-Mansur took 3,000 female and child captives, and his governor of Córdoba took 3,000 Christian slaves in a subsequent attack upon Silves in 1191.
[22] These raiding expeditions also included the Sa’ifa (summer) incursions, a tradition produced during the Amir reign of Cordoba.
In addition to acquiring wealth, some of these Sa’ifa raids sought to bring mostly male captives, often eunuchs, back to Al-Andalus.
[23] Slavs’ status as the most common group in the slave trade by the tenth century led to the development of the word “slave.”[24] During the Sack of Barcelona (985) by the Córdoban general, Almanzor, the entire garrison was slain, and the inhabitants were either killed or enslaved.
Forming relations between the Umayyads, Khārijites and 'Abbāsids, the flow of trafficked people from the main routes of the Sahara towards Al-Andalus[8] served as a highly lucrative trade configuration.
According to Roger Collins, although the role of the Vikings in the slave trade in Iberia remains largely hypothetical, their depredations are clearly recorded.
Raids on Al-Andalus by Vikings are reported in the years 844, 859, 966 and 971, conforming to the general pattern of such activity concentrating in the mid ninth and late tenth centuries.
[38] In al-Isbahani's Kitab al-Aghani, Ibrahim al-Mawsili noted that originally slave girls with dark complexion had been selected to be trained as qiyan, because they were viewed as unattractive, but that this custom had changed and white slave-girls, who were considered more beautiful and were therefore more expensive, had started to be trained as qiyan to increase their market value even more: The qiyan-slaves were not secluded from men in harem as free women or slave concubines, but in contrast performed for male guests - sometimes from behind a screen and sometimes visible - and are the perhaps most well documented of all female slaves.
[35] The writer Al-Jahiz: "the singing-girl is hardly ever honest in her passion or sincere in her affection, for she, by training and by disposition, sets traps and snares for her admirers in order that they may plung into her toils [lit.
"noose"]", and "for the most part singing-girls are insicere and given to employing deciet and treachery in squeezing out the property of the deluded victim and then abandoning him", and that their enslaver used them to assemble gifts from male guests who came to him to see and hear his qiyan slave-girl.
[43] The fact that the rulers of al-Andalus preferred and could afford to buy white European female sex slaves had the unwanted consequence that many Caliphs, who were sons of European slave concubines, became lighter in color for each generation; many Caliphs had fair complexion and blue eyes, and dyed their hair black in order to appear more stereotypically Arab.
[43][44] The harem system that developed in the Umayyad and Abbasid Caliphate, illustrated by the Abbasid harem, was reproduced by the Islamic realms developing from them, such as in the Emirates and Caliphates in Muslim Spain, Al-Andalus, which attracted a lot of attention in Europe during the Middle Ages until the Emirate of Granada was conquered in 1492.
[47] The concubines (jawaris) were educated in accomplishments to make them attractive and useful for their master, and many became known and respected for their knowledge in a variety of subjects from music to medicine.
[47] A jawaris concubine who gave birth to a child acknowledge by her enslaver as his attained the status of an umm walad, and a favorite concubine was given great luxury and honorary titles such as in the case of Marjan, who gave birth to al-Hakam II, the heir of Abd al-Rahman III; he called her al-sayyida al-kubra (great lady).
[49] The concubines of Abu Marwan al-Tubni (d. 1065) were reportedly so badly treated that they conspired to murder him; women of the harem were also known to have been subjected to rape when rivaling factions conquered different palaces.
[49] Several concubines were known to have had great influence through their masters or their sons, notably Subh during the Caliphate of Cordoba, and Isabel de Solís during the Emirate of Granada.
Either they were targeted for military slavery as slave soldiers; or they were subjected to castration and selected to serve in administration in our outside of the harem, tasks for which they were expected to be eunuchs.
Male slave children were normally taught Arabic and converted to Islam, and then selected to be trained in a future function chosen for them.
Ibn Hawqal, Ibrahim al-Qarawi, and Bishop Liutprand of Cremona note that the Jewish merchants of Verdun specialized in castrating slaves, to be sold as eunuch saqaliba, which were enormously popular in Muslim Spain.