d. 1156 · Anatolian Seljuk sultan (1116–1156)
Mas'ud I
Anatolian Seljuk sultan; during the Second Crusade he headed the Turkish forces that inflicted heavy losses on Conrad III's army near Dorylaion and on the French army crossing Mount Cadmus.
BIOGRAPHICAL DOSSIER
Life and historical role
Life and political setting
The son of Kilij Arslan I, Mas'ud took the Seljuk throne at Konya around 1116 after a struggle with his brother Malikshah. During his long reign he strengthened his state by balancing relations with the Danishmendids and Byzantium.
Role in the Crusades
In 1147 the army of the German king Conrad III was routed near Dorylaion by constant attacks of Turkish cavalry and retreated. The army of King Louis VII of France also suffered heavy losses crossing Mount Cadmus in January 1148. These clashes weakened the Second Crusade before it even reached Syria.
Historical significance and source problems
Mas'ud's reign is the period in which the Anatolian Seljuk state settled as a lasting power centred on Konya. He died in 1156 and was succeeded by his son Kilij Arslan II. Information on the crusade comes mostly from Latin sources such as Odo of Deuil and Otto of Freising; how far Mas'ud commanded the battles in person is unclear.
Biographical information is linked to the sources shown on the page and to the connected event records. Disputed dates are given as approximate, gaps are not filled by conjecture, and later literary or visual depictions are not treated as contemporary portraits.