Devsirme

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 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 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.

Started in the mid 1300s by Murad I as a means to counteract the growing power of the Turkish nobility, the practice itself violated Islamic law.

By 1648, the practice was slowly drawing 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.

The Ottoman Empire, beginning with Murad I, felt a need to "counteract the power of (Turkic) nobles by developing Christian vassal soldiers and converted kapıkulları as his personal troops, independent of the regular army." The elite forces, which served the Ottoman Sultan directly, were divided into two main groups: cavalry and infantry. The cavalry was commonly known as the Kapıkulu Süvari (The Cavalry of the Servants of the Porte) and the infantry were the popular Yeni Çeri (transliterated in English as Janissary), meaning "the New Corps".

At first, the soldiers serving in these corps were selected from the slaves captured during war. However, the system commonly known as devshirme was soon adopted. In this system children of the rural Christian populations of the Balkans were conscripted before adolescence and were brought up as Muslims. Upon reaching adolescence, these children were enrolled in one of the four imperial institutions: the Palace, the Scribes, the Religious and the Military. Those enrolled in the Military would become either part of the Janissary corps, or part of any other corps. The brightest were sent to the Palace institution (Enderun), and were destined for a career within the palace itself where the most able could aspire to attain the very highest office of state, that of Grand Vizier, the Sultan's immensely powerful chief minister and military deputy.

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Wikipedia