Slavery was a major institution and a significant part of the Ottoman Empire 's economy and traditional society. It has been reported that the selling price of slaves decreased after large military operations. In Constantinople present-day Istanbul , the administrative and political center of the Ottoman Empire, about a fifth of the 16th- and 17th-century population consisted of slaves. A smaller number of slaves also arrived in this period from the Caucasus, Africa, and other regions, but exact figures remain to be calculated.
Individual members of the Ottoman slave class, called a kul in Turkish , could achieve high status in some positions. Eunuch harem guards and janissaries are some of the better known positions an enslaved person could hold, but enslaved women were actually often supervised by them. However, women played and held the most important roles within the harem institution. Many enslaved officials themselves owned numerous slaves, although the Sultan himself owned by far the most.
Other slaves were simply laborers used for hard labor, such as for example agricultural laborers and galley slaves. Female slaves were primarily used as either domestic house servants or as concubines sex slaves , who were subjected to harem gender segregation. While there were slaves of many different ethnicities and race was not the determined factor in who could be enslaved, there was still a racial hierarchy among slaves, since slaves were valued and assigned tasks and considered to have different abilities due to racial stereotypes.
Even after several measures to ban slave trade and restrict slavery, introduced due to Western diplomatic pressure in the late 19th century, the practice continued largely unabated into the early 20th century. The institution of slavery in the Ottoman Empire was modelled on the institution of slavery in the previous Muslim empires of the Middle East: the slavery in the Rashidun Caliphate — , the slavery in the Umayyad Caliphate — , slavery in the Abbasid Caliphate — and slavery in the Mamluk Sultanate — , which in turn were all built upon slavery in Islamic Law.
Slavery was regulated by the Seriat , the religious Islamic Law, and by the secular Sultan's law Kanun , which was essentially supplementary regulations to facilitate the implementation of the Seriat law. Since all non-Muslims outside of Muslim lands were legitimate targets of enslavement, there were slaves of different races. Officially, there were no difference made between slaves of difference races, but in practice, white slaves were given the highest status, with Ethiopians second and fully black African slaves given the lowest status among slaves.
