IDRISI (Seyyid Mohammed el Idrisi), Arab chief, b. 1876 at Sabia, was a grandson of Seyyid Ahmed el Idrisi, a native of Fez, who was head of a religious fraternity or tariqa at Mecca and who acquired land at Sabia, settled there and died in 1837. The descendants of Seyyid Ahmed appear to have increased in wealth and influence and to have gradually supplanted the ruling sherifial family of Abu ‛Arish. Seyyid Mohammed was educated partly at El Azhar University and partly by the Senussi at Kufra, and subsequently resided for a time in the Sudan, at Argo. On his return to Asir, his one ambition was to render that district independent of the Turk. By able administration he gradually expanded his political power to include Mikhlaf el Yemen and a large part of the Tihama, with control over several tribes outside these limits. He threw in his lot with the Allies in the World War, and was the inexorable foe of the Imam of Yemen (see Arabia).