Standing Figure of a Ghulam / 12th-13th century, Iran
From 811 to 813, a vicious civil war pitted al-Amin and al-Mamun, the two sons of Caliph Harun al-Rashid (r. 766-809), against each other. In the end, the former was executed after a long and destructive siege of Baghdad and the latter ascended the throne. The episode generated a demand for troops loyal only to the caliph and created lasting tensions between the groups of elites who had supported each of the two brothers. Al-Mamun (r. 813-833) and his successor al-Mu'tasim's (r. 833-842) solution was the creation of a professional military made largely of enslaved boys and men originating from Turkic-speaking tribes of Central Asia, who were renowned for their skills as riders and archers. These ghilman (plural form of ghulam, servant) were expected to serve their master loyally.
After completing a formative training, a ghulam joined the elite guard as a mounted warrior. Their distinctive clothing and accessories were mentioned by medieval authors and depicted in surviving artworks such as this one. Reviews were organized every year, in which the caliph would personally assign each of his horsemen to a certain rank and pay according to his performance and receive loyalty oaths from them. This system gave the Abbasid rulers a professional army on which they could depend and, adopted by rival rulers, it lasted for centuries.
But it was not without problems. Over time, these new soldiers attained significant positions of power and influence within the ruling elite. Chroniclers of the time paint a picture of tensions caused by the presence of the ghilman in Baghdad, a situation which may have led al-Mu'tasim to relocate the armies to the new capital of Samarra. Also, the substantial costs of acquiring and maintaining this professional army ate up a great part of the caliphs' revenues. This led to financial instability in the later part of the ninth century.