Devshirme in the Ottoman Palace School

Devshirme (Ottoman Turkish: دوشيرمه‎, devşirme, literally "lifting" or "collecting"), also known as the blood tax or tribute in blood, was chiefly the practice whereby the Ottoman Empire sent military officers to take boys, ages 8 to 18, from their families in Eastern and Southeastern Europe in order that they be raised to serve the state. This tax of sons was imposed only on the Christian subjects of the empire, in the villages of the Balkans and Anatolia.

The boys were then forcibly converted to Islam with the primary objective of selecting and training the ablest children and teenagers for the military or civil service of the empire, notably into the Janissaries.

Devshirme started in the mid 1300s under Murad I as a means to counteract the growing power of the Turkish nobility. According to Alexander Mikaberidze the practice violated Islamic law. Mikaberidze argues that the boys were "effectively enslaved" under the devshirme system, and that this was a violation of the dhimmi protections guaranteed under Islamic law. This is disputed by scholars of Ottoman history, including Halil İnalcık, who argues that the devshirme were not slaves.

By the middle of the seventeenth century, the practice formally came to an end. An attempt to re-institute it in 1703 was resisted by its Ottoman members who coveted its military and civilian posts. Finally in the early days of Ahmet III's reign, the practice of devshirme was abolished.

The Devshirme came up out of the kul system of slavery that developed in the early centuries of the Ottoman Empire and which reached this final development during the reign of Sultan Bayazit I. The origin of the kuls was mostly prisoners from war, hostages or slaves that were purchased by the state. An early Greek source mentioning devshirme (paidomazoma in Greek) is a 1395 speech of the Archbishop Isidore of Thessalonica. The speech meant to comfort the parents of young boys abducted after orders of sultan Bayezid I.

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