Slavery () was practiced in Malta from classical antiquity to the early modern period, as was the case in many countries around the Mediterranean Sea. Sources dating back to when the islands were under Arab Muslim rule during the Middle Ages attest to the presence of slavery but lack details regarding the slaves' ethnic and religious backgrounds. When the islands were part of the Kingdom of Sicily during the late medieval period, it is apparent that many black Africans were domestic slaves on the islands.

The institution of slavery in Malta reached its apex during the period of Hospitaller rule between 1530 and 1798, when it took on unprecedented proportions and was largely maintained through commerce raids against enemy shipping and coastal targets by the Hospitaller navy and Malta-based corsairs. This led to an influx of mostly Muslim prisoners as slaves, but there were also lesser numbers of Jewish, Christian and black African slaves on the islands. Some were forced to work as galley slaves while others worked on land as labourers and had a variety of duties ranging from manufacturing to domestic roles.

Around the same time, there were Maltese people enslaved in North Africa and the Ottoman Empire after being captured during attacks on the islands or on Christian shipping, including in raids by the Barbary corsairs. Thousands were enslaved en masse during a major attack on Malta in 1429 and one on Gozo in 1551; these and other raids had a lasting impact on the islands' demographics and folklore.

When Hospitaller rule ended with the French occupation of Malta in 1798, slavery was abolished through a decree by Napoleon. Although French rule in Malta was short-lived, the abolition was upheld and confirmed by local rebel authorities in 1800 and by the British protectorate in 1812.

Antiquity and Middle Ages Slavery existed in the Maltese Islands from antiquity. Successive powers that controlled the archipelago prior to the arrival of the Hospitallers in 1530—including the Romans, Byzantines, Arabs and Sicilians—all using slave labour.

Roman rule After the Roman Republic captured Malta from the Carthaginians during the Second Punic War in 218 BC, prisoners who were not of noble birth were sold as slaves in Lilybaeum, Sicily.

Arab rule

Malta was conquered by the Aghlabids in 870 AD, and during the conquest the islands' main settlement of Melite was destroyed and its inhabitants were massacred. It is possible that the islands were depopulated for some time after this attack, and what remained of the islands' pre-870 Christian population might have converted to Islam, become dhimmi, or were enslaved.

According to the chronicler al-Himyarī, in 1048–1049 a Muslim settlement which became the city of Mdina was established on the site of Melite. The settlers included at least a few hundred slaves, and while sources do not specify their ethnicity or religion, it has been speculated that the slaves might have been Arabic-speaking Sicilian or Slavic Christians, or recent converts to Islam from Christianity. They might have also assimilated any surviving descendants of the indigenous population who had survived the events of 870 AD.

In 1053–1054, these slaves aided the Muslim settlers in successfully repelling a Byzantine attack, and were granted freedom as a result. Al-Himyarī stated that at the time the Muslims had around 400 fighting men, but were outnumbered by the slaves.

After the successful Norman invasion of Malta occurred in 1091, the Normans freed many Christian slaves from Malta and took them to Sicily, after which the freed slaves crossed the Straits of Messina and returned to their homelands. Surviving sources once again do not specify the ethnicities of these slaves, but it has been speculated that they might have been from mainland Italy or Greece.

Kingdom of Sicily In the late medieval period, maritime brigandage was widely practiced throughout the Mediterranean, and the Maltese Islands were used as a base for corsairing by the Genoese. In the 13th century Genoese corsair Enrico Pescatore ruled the archipelago as Count of Malta. Genoese and Maltese corsairs added human captives to their loot, including black Africans who had been previously enslaved.

Maltese documents attest to the presence of domestic slaves in the 13th and 14th centuries. For example, a Greek slave woman, Catherina, was emancipated through a notarial deed dated 23 January 1342. However, it seems that prior to the beginning of Hospitaller rule in 1530, the majority of domestic slaves in Malta were black Africans, usually described in sources as Ethiopians. These may have been captured by Maghrebis along the southern border of their territories.

By the end of 15th century, there were such slaves in the service of wealthy families in Mdina as well as in the countryside and in Gozo, where for example the priest Pietru Mannara sold a slave named Ferha to a compatriot. There appears to have been a custom of baptising slaves upon their arrival to Malta.

Hospitaller rule Malta was ruled by the Knights Hospitaller, also known as the Order of St. John, between 1530 and 1798. During this period, slavery was widely practiced in both Christian and Muslim-ruled parts of the Mediterranean, and it was regarded as an ethically acceptable institution which was regulated by governments. Slavery was seen as a source of labour, and it formed a key part of Hospitaller Malta's economy.

Corsairing

Corsairing () was a pivotal part of the Maltese Islands' economy throughout the period of Hospitaller rule. The majority of slaves in Hospitaller Malta were acquired during corsair raids on enemy shipping or coastal targets, and this economic-military model allowed the system of slavery to be maintained from the 16th to the 18th centuries. Malta's capital Valletta has been described as one of the Mediterranean's key centres for corsairing during the early modern era, similar to Livorno and their Muslim counterpart Algiers.

The Order would issue letters of marque allowing private ships to fly its flag and capture enemy shipping in their name, taking captured ships' cargo as plunder and their crews as slaves. These corsairs included both native Maltese and other Europeans, such as Italians, French and Spaniards. Some wealthy Hospitaller knights who owned their own vessels—such as Hugues Loubenx de Verdalle and Alof de Wignacourt, both of whom rose to lead the Order as Grand Masters—also personally participated in corsairing.

In addition, the Hospitallers maintained their own fleet of galleys and other vessels which would be sent out each year to pursue Muslim merchant shipping and raid undefended coastal settlements. During the 16th and 17th centuries they raided as far as the Eastern Mediterranean, capturing ships headed from Alexandria and Levantine ports to the Ottoman capital of Constantinople. The Hospitaller fleet raided isolated garrisons and settlements along the North African coast as well as in Greece and Anatolia. Following the fall of Candia to the Ottomans in 1669, the Hospitaller fleet and Malta-based corsairs tended to limit their activities to the western and central Mediterranean, directing their efforts towards fighting their Muslim rivals, the Barbary corsairs.

By the 18th century, corsairing was on the decline in much of the Mediterranean, but the practice persisted in Malta even as other ports reoriented themselves towards safer and more lucrative economic activities such as trade. The Hospitallers used the pretext of a perpetual holy war against Islam as a justification for their corsairing activities, but in practice captains of ships were ordered to sail the seas and plunder for profit. Even Christian Greek ships could be captured under the pretext that they were schismatics trading with the Turks.

Slave trade From 1530 to 1551, the Hospitallers also ruled Tripoli on the North African coast, facilitating the importation of black African slaves from North African slave markets to nearby Malta and Sicily. There are also records of French ships carrying black slaves from North Africa to Ottoman slave markets stopping at Malta during the 18th century.

People captured by the Hospitaller fleet or by corsairs during raids were considered to be slaves, and when cargo of captured ships included black Africans who had already been slaves, these would simply change ownership, while their former masters also became slaves. Like all other travelers arriving to Malta from the sea, slaves were initially quarantined upon ships or in the Lazzaretto of Manoel Island. The captives were then triaged according to sex, age and robustness, these qualities being assessed in order to determine their market value. If the slaves were captured by a ship belonging to the Order, the knights decided their respective destinations: the galleys, domestic service, gift or sale. If they had been captured by a licensed ship, the captain would pay the Order a certain percentage before disposing the balance as he pleased.

Slaves in Malta were viewed as saleable objects, and were referred to as merchandise in the penal code of 1724. They were auctioned off at a public slave market in Valletta, which was situated at Piazza San Giorgio, the city's main square in front of the Grandmaster's Palace. At the time, similar markets also existed in Christian Mediterranean ports such as Genoa, Messina, Livorno and Naples. Slaves were also traded abroad or could be given as gifts; for example several female slaves were gifted by the Hospitallers to the vice-reine of Naples between 1637 and 1655. The English Royal Navy considered purchasing slaves from Malta for its Mediterranean Fleet in the 17th century, while the Papal Navy regularly bought Muslim slaves from anyone who could provide them, including from the Hospitallers. 100 slaves were sent to the Pope in 1662 for service in his navy, while 40 others were presented to the Pope in 1720 after the Ottoman sultan requested the Papacy to send Muslim slaves to repair the Church of the Holy Sepulchre in Jerusalem.

In around 1660, more than 700 slaves were disembarked on the island, 538 of whom were quickly sold for an average price of 142 scudi for a man and 159 scudi for a woman. Prices continued to increase until the beginning of the 18th century, then stabilised as demand for galley slaves decreased by the middle of the century as the great powers, including the French Navy, dismantled their galley fleets. Despite this, the Hospitaller fleet in Malta continued to use galley slaves until the end of the century.

An example of how the slave trade operated in practice can be seen in the events that occurred after the 1685 siege of Coron in the Peloponnese, in which the Hospitallers supported the Venetians against the city's Ottoman defenders. Official figures indicate that after the city surrendered, 1,336 Turkish and Jewish inhabitants were taken as slaves and were divided between the various members of the Christian coalition, with the Hospitallers taking 223 captives. Despite this, the knights, soldiers and seamen of the Order's fleet clandestinely carried away more captives into slavery, bringing the total number to more than 500. Some of the captives were sold at Italian and Sicilian ports, including Gallipoli and Augusta, while the rest reached Malta in September 1685. At this point the Order declared that all slaves belonged to its Treasury and initiated proceedings against individuals who had clandestinely kept slaves for themselves or who had sold them without the Order's permission. The Order's records indicate that 284 slaves were consigned to its Treasury.