HistoryThe various nomadic tribes of Turks reigned over Anatolia under the guise of subjects of the Seljuk Empire; however, after the death of Alp Arslan in 1073, the Seljuk empire splintered into many rebel states. In 1080, Jalal ad-Dawlah came to power over the city of Iconium (Konya) and became its Sultan; his rule was immediately contested by other warlords in Asia Minor. He had control over the cities of Iconium, Caesarea, Mosul, and Yerevan, but his rule was disputed by other beyliks (principalities ruled by "beys", or "governors") as well as by the Byzantine Empire, the Emirate of Tbilisi, and the Abbasid Caliphate.
Jalal began his campaigning almost instantly after assuming control over much of the former Seljuk Empire. In 1094 he took control of the city of Trebizond from the Trebizond Empire, only the first step in his conquest of the rivals. His generals in Yerevan and Mosul carried out their own campaigns, with Baghdad and Tbilisi falling to their armies by 1100. Jalal died in 1108, and was succeeded by his son Mustafa ad-Dawlah.
Sultan Mustafa dragged on his father's conquests, taking control of the Sultanate of Damacus and the Sultanate of Acre in a series of campaigns that ranged from the 1120s to 1130s. In the 1140s and 1150s he fought against the Byzantine Empire, who launched an invasion of Anatolia in 1146. The Rum repulsed the Byzantine attacks and captured Smyrna and Nicaea in a counterattack. As a result, the Seljuks were made the bastion of Islam in the Middle East, and this brought them into conflict with the Crusader States (fighting the Spanish crusaders first).