‘Izz al-Dīn Qilij Arslān I (Turk. Izzüddin Kiliç Arslan I) was the third ruler of Rûm (1092-1107), the sultanate established by a branch of the Saljûq dynasty in western Anatolia.
Qilij Arslān I was the son of Sulaymân I ibn Qutlumush, the founder of the Rûm sultanate. When Sulaymân died in combat at Shaizar in Syria (c. 1086) fighting against the Great Saljûq sultan Malik Shāh I and his brother Tutush I, ruler of Syria, the young Qilij Arslān was among the captives and spent some years in captivity in Baghdad, during which time his sultanate was ruled by his uncle Abu’l Qāsim (10861092). Qilij Arslān’s liberation following Malik Shāh’s violent death (1092) coincided with Abu’l Qāsim’s death in Nicaea at the hands of Malik Shāh’s agents, and so QilijArslān managed to ascend his throne. From the outset of his reign he established contacts with the ambitious emir of Smyrna (mod. Izmir, Turkey), Chaka, whose son-in-law he became, while his belligerent activities were directed against the Dānishmendids in eastern Anatolia.
In August 1096 Qilij Arslān’s troops decimated the rabble of Peter the Hermit, who were the first crusaders to cross into Asia Minor. The following year, while he was engaged besiegingDānishmendid Melitene, Qilij Arslān’s capital of Nicaea (mod. Iznik, Turkey) was besieged by the combined armies of the First Crusade (1096-1099) and the Byzantines. The Byzantines became masters of the city and of the sultan’s wife and family, despite his attempt to relieve the city (May-June 1097). However, the Byzantine emperor Alexios I Komnenos soon returned the captives to the sultan, who, now in coalition with theDānishmendids, confronted the crusaders at Dorylaion (17 July 1097), suffering a grave defeat, while the Byzantines were restoring several of their Anatolian possessions.
Having lost his capital, Qilij Arslān selected Ikonion (mod. Konya, Turkey), which was to become his new headquarters early in the twelfth century, though it seems that the actual transferral of the new Rûm Saljûq capital was associated with his successors Malik Shāh II (1107-1116) or Mas‘ûd I (1116-1155). He allied with the Dānishmendids in two victorious battles against the Crusade of 1101 at Mersivan and Herakleia (mod. Eregli, Turkey); Bohemund I of Antioch was captured in these engagements and was released by the Dānishmendids in 1104.
In the last eventful period of his reign Qilij Arslān was persuaded by Alexios I (to whom he even sent mercenaries against the Norman invasion of Greece under Bohemund in 1107) to eliminate his father-in-law Chaka (c. 1105-1106), while the death of the Dānishmendid emir (c. 1104) caused him to resume his aggression against the latter’s possessions. In 1106 he captured Melitene (mod. Malatya, Turkey) and Marty- ropolis (mod. Silvan, Turkey), and in 1107 he seized Mosul. However, when he attempted an invasion of Mesopotamia, he faced a massive coalition under the Great Saljûqsultan Muhammad I (1105-1118) and was killed in action in a hotly contested battle at Khabur River on 3 July 1107, which was to assume legendary proportions in early Turkish epic.