What is interesting in the case of the Ottoman Empire is that slaves within its borders could occupy any social position in society—from galley rower to Grand Vizier. This makes the description and study of slavery in the lands of the Crescent a very complex task. The different categories of slaves in the Ottoman Empire had varying social statuses, lived under a wide range of conditions, and were divided into numerous subcategories according to their racial, ethnic, and religious background. It is important, in this context, to avoid any generalization of slavery and slaveholding in the empire, as this would lead to serious inaccuracies in understanding and evaluating historical reality.

Types of Slaves and Their Fate

The main types of slaves in the Ottoman Empire were:

• The “Servants of the Porte” (kul),
• Agricultural slaves,
• Urban slaves, and
• Those engaged in the harshest forms of labor—in mines and on galleys.

Each of these categories had a specific set of rights and obligations. The simplest formula we can derive is that the farther the slaves were from the major cities, the harsher their lives. Female slaves lived in significantly worse conditions than male slaves, and black slaves were at the lowest rung of the racial and ethnic ladder.

Undoubtedly, the most privileged class of slaves were the so-called “servants of the Porte”—those under the direct authority of the Sultan. As his personal property, they held a high place in the social hierarchy and could occupy key military and administrative positions—pashas, aghas, viziers, provincial governors, etc. This category also included the concubines of the Sultan’s harem, who could be freed and recognized as wives, as in the famous case of Roxelana. The Porte’s slaves were divided into several subcategories, including: the Janissaries, the Sultan’s sipahis, palace guards, harem guards, the harem itself, and a large part of the state administration recruited through the “blood tax” (devshirme).

Urban slaves were those engaged in various tasks in households throughout small and large settlements. They ranged from domestic servants to workers in workshops, taverns, caravanserais, and artisans’ shops. Slaves were also found among porters serving merchants and markets. Their fate varied depending on the nature of the household and the type of work they did. Generally, the more valuable their labor, the better their living conditions.

Agricultural slaves worked in various types of farming and animal husbandry. Their quality of life was directly proportional to the quality of their work and the prosperity of the estate where they were employed. Nevertheless, their lives were harder and more labor-intensive than those of urban slaves, and their working conditions were often appalling by today’s standards—sometimes comparable to those on New World plantations.

Without question, the most unfortunate were those condemned to the harshest physical labor—working in mines or rowing galleys. Their work resembled penal servitude, associated with constant danger to life, horrible living conditions, and unrelenting abuse by their masters. Even though conditions improved somewhat over time, they remained the most despised of all slave categories.

Sources of Slaves

Throughout the Ottoman period, slaves were obtained by several main methods. The primary source of slaves was the capture of prisoners of war and the enslavement of part of the conquered population. Logically, this was the main method until the end of the 16th century, as the Ottoman Empire was constantly expanding. Every victorious battle, successful campaign, and conquered territory brought streams of slaves to the Porte, one-fifth of whom belonged personally to the Sultan (pençik). Slaves were part of the spoils of war and were distributed as rewards to soldiers—whether regulars, provincial troops (timariots), or mercenaries (akıncı, levend, sekban). Usually, soldiers sold captured enemies and enslaved locals at slave markets for profit, and the slaves would then be absorbed into the categories mentioned above.

Besides military capture, slaves were also obtained through trade—by purchasing them from Africa, the Middle East, and Eastern Europe, and reselling them within the empire. This method became increasingly important as Ottoman expansion slowed. After 1700, it became the main method of acquiring new slaves.

Another method was internal raiding by militarized elements against the rayah (non-Muslim subjects). Such acts were illegal under Ottoman law, but after 1600, it became increasingly difficult for the central authority to control local derebeys (lords). The enslaved victims were sold to “insider” slave traders who didn’t ask questions about their origin, laundering the transactions and integrating the slaves into the system. These raids, though technically illegal, also occurred before 1600—especially during military campaigns. However, the central government generally sought to stop such practices, as they deprived the empire of taxpayers.

Debt slavery was another method. Under heavy taxation due to poor harvests or as punishment for certain crimes, subjects could find themselves enslaved. The sale of people to pay off debts is as old as civilization and has been present in all human societies.

The Devshirme System

A special system for recruiting slaves for the Sultan’s household was the devshirme. This tax, imposed on non-Muslims—especially Christians—was part of a long-standing Islamic tradition of securing loyal servants torn from their origins and fully dependent on their new master, who alone guaranteed their lives and rights.

Devshirme was collected by district (sanjak) from around 1400 to 1730. In the mid-16th century, Suleiman the Magnificent allowed it to be collected from Muslims as well, which drastically reduced the burden on Christians. It was collected once every 6–7 years, always from different regions, to avoid harming population growth. There were other restrictions—children of widows/widowers, only sons, married boys, or children from privileged settlements were exempt. Each levy gathered about 3,500 boys aged 10–13, without physical or mental defects.

These restrictions were cleverly used by locals to protect their children. In poor areas, some parents gave up their children voluntarily to spare them from starvation or reduce household costs. Like other aspects of slavery, devshirme cannot be simplistically defined in terms of social hardship.

Fate of the Slaves

As mentioned, slaves lived a wide variety of lives, and the severity of their status depended on where and how they served. It’s worth noting a few more facts about their lives:

• Following sharia law, slavery in the Ottoman Empire was rarely lifelong. In most cases, owners were expected to free their slaves after 7–10 years and help them integrate into society.
• A key exception was the Sultan’s slaves, who, despite their privileges, remained property of the Sultan for life.
• Slaves were not bred for reproduction—children born to female slaves were born free.
• If a concubine bore a child to her master, he had to care for her, could not sell her, was responsible for the child, and upon his death, the woman was freed. Concubines could also become legal wives.
• Slaves could be freed through marriage (e.g., free person marries a slave), and owners often encouraged freed slaves to marry, seen as a charitable act in line with Islamic principles.
• Debt slaves could buy their freedom after fulfilling their term, and owners were forbidden from selling them during this period.

Ethnic Composition of Slaves

In the 14th–15th centuries, most slaves came from Bulgarians, Greeks, Serbs, and Hungarians. Later, under Mehmed the Conqueror, Serbs, Bosnians, Hungarians, Albanians, Vlachs, and Ukrainians became the main sources. From the time of Selim I, Ottoman markets increasingly included African and Middle Eastern slaves. This diversity persisted until the late 17th century. After 1700, most slaves came from Africa, the Middle East, and the Caucasus—Georgians, Circassians, and others.

Bulgarians dropped from the list of heavily affected groups relatively early, but that doesn’t mean they were untouched. Especially during the Kardzhali period and the turbulent early 17th century, there were cases of enslaved Bulgarians. Given the ongoing emancipation of slaves, a significant portion of the Ottoman population in the 18th–19th centuries were descended from freed slaves. This applied to both cities and provinces, as freed slaves could return to their native regions.

A comparison can be made with the Roman Empire, where in the Augustan era, between 15% and 30% of the population were descendants of freed slaves.

Volume of Trade and Key Markets

It is hard to determine exactly how many slaves were sold in the Ottoman Empire between 1400 and 1870. It is believed that in the 19th century alone, over 1,300,000 slaves were sold. According to estimates by Halil Inalcik, between 1500 and 1700, about 2,000,000 slaves entered the empire from Poland, Ukraine, and Russia. Other studies indicate that about 1,500,000 slaves came from the Mediterranean between 1530 and 1780. To this must be added the African and Middle Eastern slaves.

Overall, it is estimated that over 6–8 million people passed through the slave markets of the Ottoman Empire during its 470-year history (1400–1870), taken both from newly conquered lands and imported from beyond the empire.

Major slave markets emerged in the 15th century in Constantinople, Thessaloniki, Skopje, Edirne, Bursa, Damascus, later joined by Kaffa and Azov, and eventually Alexandria and Smyrna.

Ottoman slave-holding and the Bulgarians

As is evident from this brief overview, slavery in the Ottoman Empire was an extremely complex phenomenon, not subject to simplistic historiographical interpretation or popular judgment.

One thing is certain: Bulgarians, for the most part, were not enslaved after 1400, mainly because their lands were at the heart of the empire and formed the main hinterland of its capital. As the wealthiest region in the empire, the Porte sought to preserve the local Bulgarian population as taxpayers and usually did not permit their enslavement.

However, slavery remained present in Bulgarian territories—especially in cities and the estates of wealthy provincial elites. The devshirme was collected from Bulgarian lands until 1704, meaning that Bulgarians contributed to the Sultan’s court administration and regular troops. Between 1390 and 1704, probably 40,000 to 50,000 Bulgarian youths were recruited through the devshirme to serve as “servants of the Porte.”