As illustration are added some paintings of Eunuchs garding the entrance from several mss. 


Sadr al-Din al Husayni: Akhbar al-dawla al-Saljuqiyya. 
(end 12th century) (history of the nation of the Saljuqiyya) from Iran
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Taken from: Iranica.com

                  The History of the Seljuq State: Clifford Edmund Bosworth


Also called: li- Sadr al-din Abi al-Hasan'Ali b. Nasir al-Husayni : Akbar al Dawla al-Salguqiyya.
Saadr al-Din Haosayn : Akobar al-dawla al-saljuqiya.

 

During Saljuq times (1) black slaves continued being imported into Persian lands.

Zangi (2) (the Salghurid atabeg (3) of Fars named Zangi ruler of Shiraz) sent with his envoy to the sultan (Arslan B. Togril)(4) and the Atabeg Ildegiz (or Eldiguz)(5) (in ca 1169) gifts, presents, charitable donations, rare items, various items of clothing of all kinds, castrated Habashi slaves, ghulams, (al-gelman al-haobuoe men al-koesayan) (ie from East Africa according to the translator) and Arab horses which he purchased from al-Qatif (in Saudi Arabia on the Persian gulf) and the Arab lands.

 
Note:Since the presents sent with these included Arabian horses from Qataf, it would appear that these slaves were brought from East Africa to the Persian Gulf ports. There are no indications as to where they were castrated.

(1) The Seljuk dynasty, was an Oghuz Turkic, Sunni Muslim dynasty that gradually became Persianate and contributed to the Turco-Persian tradition in the medieval Middle East and Central Asia. The Seljuks established the Seljuk Empire (1037–1194),

(2) This must have been Zangi ibn Mawdud (1161–1178) if the dating of 1169 is correct.

(3) The Salghurids, also known as the Atabegs of Fars, were a Persianate dynasty of Salur Turkmen origin that ruled Fars, first as vassals of the Seljuqs then for the Khwarazm Shahs in the 13th century.

(4) Toghril b. Arslan (r. 1176-94) last of the Great Seljuq rulers of Iraq and Persia.

(5) Atabeg Ildegiz (or Eldiguz): The Ildegizids, were a Turkic dynasty (founded by Eldiguz of Kipchak origin) which controlled most of northwestern Persia, eastern Transcaucasia, most of Azerbaijan, and Djibal. Down to the death in war 1194 of Sultan Toghril b. Arslan, last of the Great Seljuq rulers of Iraq and Persia, the Ildenizids ruled as theoretical subordinates of the Sultan.