ABSTRACT
At this time the sultan was elzz al-Din Kay-Ka'us II, the son of Ghiyath al-Din Kay-Khusraw II by a Greek mother. He succeeded his father in 1245 but spent much of his reign struggling against his two halfbrothers: Rukn al-Din Qilich Arslan IV, the son of a Turkish woman, and eAla' al-Din Kay-Qubad II, whose mother was a Georgian princess. elzz al-Din was supported by his step-father, Shams al-Din alI~fahani, who was unable, however, to prevent Rukn al-Din and his party from establishing themselves in the eastern half of the country. I~fahaniwas murdered in 1249, but later that year elzz al-Din defeated Rukn al-Din and reasserted himself as the sovereign, although the government was nominally carried on in the names of all three brothers. See Cahen, Pre-Ottoman Turkey, pp. 271-9; Lindner, 'The challenge of Qt.hch Arslan IV', pp. 411-17. Rukn al-Din then subsequendy made another bid for the throne, but was again crushed and imprisoned (above, p. 277). Rubruck is one of our principal sources for the Seljiiks; it should be noted that Simon of Saint-Quentin, pp. 82-3, 85 (Vincent of Beauvais, XXXII, 26 and 28), who is another valuable authority, relates the events of 1245-c. 1250 in a confused fashion, making Rukn al-Din the eldest and the son of a Greek mother, and ascribing to him the role of elzz al-Din.
