The reign of Sultan ‘Alā’ al-Dīn Kayqubād (1219-1237) is depicted by both mediaeval and modern sources as the apogee of the Saljūq Sultanate of Rūm (Anatolia) (c. 1081–1308). The later court historian, Ibn Bībī, reflected subsequent generations' perception of ‘Alā’ al-Dīn when he recorded that “the earth has never borne a king the like of him, nor have the high heavens looked down on such a one”. Above all, his reign was remembered for the great military conquests that unified much of Anatolia under Saljūq rule. To the north, south and east neighbouring principalities, both Muslim and Christian, were either annexed outright or reduced to tributary status in a series of memorable campaigns.