states and Christians in Muslim states, and everyone was allowed to enslave pagans.
In addition to the expectation that slaves must come from different religious backgrounds than their masters, there was also an expectation that slaves would convert to the religion of their masters and that such conversions did not require manumission.57 On the Islamic side, jurists permitted the forcible conversion of certain types of people, including women, children, and prisoners of war.58 Converting slaves without manumission was thus legally straightforward. On the Christian side, canon law considered forcible conversions invalid because the sacrament of baptism required an intention to convert on the part of the person baptized. Late medieval missionaries, however, argued that masters with pious intentions could baptize enslaved children because they did not yet have the ability to form intentions or make binding vows themselves.59 Still, manumission was not required, because the conversion of a slave was not an act of free will and because slavery was closely associated with sin. As explained by Franco Sacchetti, the son of a free Florentine man and a slave woman, “he who does not believe in the reward of Christ ought not to be free … for the most part they are like oxen to baptize. He does not even agree to become Christian through baptism. One is not held to free him, although he may be Christian, if he does not desire it. I do not say, that if he seems good and has the will to be a good Christian, that you do not do [an act of] mercy by freeing him, just as it would be bad and a sin, having a slave man or woman of guilty condition, as the greater part are, although he might be Christian, to free him.”60 In other words, converted slaves should remain under the paternalistic control of their masters for their own moral good.
The apparent simplicity of slavery based on religious difference was complicated by sectarianism. The Sunni–Shiʿite split within Islam was used to justify enslavement during the Ottoman era but not under the Mamluks.61 More important to late medieval slavery was the Catholic–Orthodox split within Christianity. Although the schism had begun in the eleventh century over such issues as papal primacy, the addition of filioque to the Nicene Creed, and the use of leavening in eucharistic bread, bitter hostility between ordinary Catholics and Orthodox did not arise until the thirteenth century.62 In the wake of the Fourth Crusade, Catholic powers including the papacy, the newly created Latin Empire of Constantinople, and Frankish states in the Aegean all adopted crusading as their framework for interacting with the Orthodox. Crusade preaching spread the image of the schismatic Greek, and repeated campaigns in the Aegean hardened attitudes on both sides. At the same time as Catholic crusades began to target Orthodox people, the Aegean was being colonized by Genoa and Venice and raided by Catalan and Turkish pirates. Both processes generated large numbers of captives.
In theory, Catholic and Orthodox Christians should not have enslaved one another no matter how much they hated each other. In practice, they did enslave one another, although Catholics had the upper hand and therefore enslaved more Orthodox than the reverse.63 In the early fourteenth century, after the restoration of the Byzantine Empire in Constantinople, Byzantine authorities complained vigorously about this. Patriarch Athanasius I wrote to the Byzantine emperor in 1303–1305 about the misery of Greeks captured by Turks and Italians, “those who escape half-dead from the Ishmaelites and the very Italians … who were able to take them into captivity on account of the magnitude of general lawlessness, their disregard for God, and their scorn and neglect of the divine commandments.”64 Emperor Andronicus II Paleologus protested to Genoa in 1308 that “certain Genoese induced certain Greek boys and girls from Constantinople and from other countries in Romania [i.e., Greek territory], promising to do many good things for them, if they would come to Genoa with them. Many boys and girls came, and when they were in the city of Genoa they sold them as slaves, which is unjust.”65 In response, Genoa’s colonial governor in Pera agreed to declare the enslaved Greeks free and permit them to leave. Andronicus II also wrote to Venice in 1319 to complain that Venetian pirates were selling Greeks as slaves in Rhodes and Cyprus.66 In 1339, Andronicus III Paleologus sent envoys to Pope Benedict XII to discuss ecclesiastical union and an alliance against the Turks. Among various proposals for improving Catholic–Orthodox relations, he asked the pope to order that “all Greeks who were sold by Latins, wherever they are, should be freed, and in addition that Greeks should not be sold, and if certain people buy or sell them, or go against them, they should be excommunicated.”67 Benedict XII ignored this suggestion.
Most fourteenth-century Catholics seem to have felt that Orthodox people deserved enslavement. An anonymous English pilgrim in the 1340s observed that because the Orthodox priests of Cyprus did not accept papal primacy, “their punishment, when captured, is life servitude (perpetua servitus), nor does the Church of Rome, although it is a work of charity to ransom slaves (servos), lift a hand for their liberation.”68 Another pilgrim in the 1340s, Niccolò of Poggibonsi, also used Orthodox rejection of papal primacy to justify their enslavement:
The Greeks hate us Latins more than they hate the Saracens, and through this great hatred they are separated from the Roman Church. As we make the pope, the vicar of God, to be the head of the Roman Church for Christians, likewise the Greeks make a vicar for themselves. In the place of the pope, they make the patriarch of Constantinople, and he makes the bishops.… Every Sunday the pope communicates with all those who obey him; but the pope treats them [the Greeks] in this way, that he allows others to take them and then sell them as slaves. And many times I saw merchants who had a great line, and they led them thus to sell at the market, as they do beasts; and when a merchant wants to sell this sad merchandise, he has them cried by the auctioneer; and whoever offers the most money, to him they are sold. O Greeks, who were masters of the world, and now are made slaves, resold throughout the world, priced like beasts!69
The early fourteenth-century crusade propagandist William of Adam offered a more moderate expression of this position: the pope did not have a pastoral duty toward Orthodox Christians but nevertheless deplored their enslavement by Muslims.70
Controversy over Catholic ownership of Orthodox slaves continued into the fifteenth century. In 1388, the bishop of Barcelona persuaded King John I of Aragon to restrict ownership of Greek slaves, but in 1401, the city council of Barcelona obtained a privilege from Pope Martin I that not only permitted ownership of Greek slaves but also prevented slaves “of the nation of the Greeks or who are Armenians, Albanians, Russians, Bulgars, Walachs, or from the parts or regions subject to the emperor of Constantinople” from challenging their status in court.71 An envoy from John VIII Paleologus to Venice in 1418 protested that a Venetian man in Modon was selling Byzantine subjects to the Catalans and holding others for ransom.72 The Venetian Senate denied the claims on the basis that its castellan in Modon would never allow such behavior. Bans by later popes on the sale of Greek slaves were quickly revoked.73 In the 1430s, a Burgundian visiting Constantinople reported that the Greeks “had reached the point of damning the Pope who had held a general council in which they were declared schismatics and damned and that they were a race of slaves (tous fussent serfs à ceux qui estoient serfs).”74
Although the status of Greek slaves attracted the most attention and debate, the majority of Orthodox slaves owned by Catholics were not Greek. In fifteenth-century Genoa, for example, Russians and Circassians were the two most common categories of slaves.75 Russians had adopted Orthodox Christianity in the tenth century, around the same time that Scandinavians had adopted Catholicism. Orthodox Christianity was also well established in the Caucasus.76 The kingdom of Georgia was a regional bastion of Orthodoxy, although it also had suzerainty over small Muslim principalities, such as Samtzkhe. Coastal Circassian and Abkhaz communities maintained close ties with Constantinople. Inland, however, the situation was murkier. Circassian and Abkhaz nobles treated religious allegiance as a political decision and could therefore be flexible about their professions of faith. During the fourteenth century, as Genoa established hegemony in the Black Sea, a few professed Catholicism.77 Circassian and Abkhaz villagers practiced a syncretic religion that blended Orthodoxy with animism. They decorated sacred trees with crosses and attached the attributes of older deities like Merise, the goddess of bees,
