Sultanate of Rüm: Encyclopedia II - Sultanate of Rüm

In the 1070s, Süleyman Ibn Kutalmish, a distant cousin of Malik Shah, the ruler of Great Seljuk, rose to power in western Anatolia. In 1075, Süleyman captured the Byzantine cities of Nicaea (Iznik) and Nicomedia (Izmit). In defiance of Malik Shah, he declared himself sultan in 1077 and established the capital at Nicaea. The Sultanate expanded, but when Süleyman was killed in Antioch (Antakya) in 1086 by Tutush I, the Seljuk ruler of Syria, the dynasty saw a certain end when Süleyman's son Kilij Arslan was imprisoned. When Malik Shah died in 1092, Kilij Arslan was released and immediately re-conquered his father's territories. He was eventually beaten by Crusaders in 1097 and was driven back into Anatolia where he established his state around Iconium (Konya). In 1107 he captured Mosul but died the same year fighting Mehmed Tapar, son of Malik Shah.

Konya had been captured by another Malik Shah but was taken by Kilij Arslan's son Mas'ud in 1116 with the help of the Danishmends whose land eventually was included in the sultanate. At the death of Mas'ud in 1156 the realm included almost all of Anatolia. Izz ad-Din Kilij Arslan II (1156–1192), the son of Mas'ud, conquered the last remnants of the Danishmends in 1174 after the death of Nur ad-Din, who had proclaimed eastern Anatolia and Armenia a protectorate. A Byzantine invasion of Manuel I Comnenus was thwarted at the Battle of Myriocephalon on September 17, 1176. The German warriors of the Third Crusade occupied Konya in 1190. With the foundation, in 1198, of the Crusader State of Cilicia (Armenia Minor), the sultans of Konya had got a Christian neighbor.

After the death of the last sultan of Great Seljuk, Toğrül III, in 1194, the Seljuks of Rüm became the sole representatives of the dynasty. Ghiyath ad-Din Kay Khusrau I seized Konya in 1205 and proclaimed himself sultan for the second time of his life. Under the rule of Kay Khusrau and his two successors, Izz ad-Din Kay Ka'us I (1211–1220) and Ala ad-Din Kay Qubadh I (1220–1237), the Seljuks of Rüm reached the zenith of their power. Kay Khusrau's most important achievement being the capture of the harbour of Attalia (Antalya) on the Mediterranean coast in 1207. Kay Ka'us captured Sinope and made Trebizond a vassal in 1214 and subjugated Cilicia, though he was forced to surrender Aleppo to Saladin in 1218. Kay Qubadh conquered the Mediterranean coast from the Byzantines in 1221 to 1225. In 1225 he also sent an expeditionary force across the Black Sea to Crimea. In the east he defeated the Mangujakids and Artuqids.