Despite the Zaydi frontier of the uprising, many devoted Shi'ās were involved.

Despite the Zaydi frontier of the uprising, many devoted Shi'ās were involved. The leader of the insurgents was Yahya b. 'Umar who was assassinated (250 A.H.) while he was praised by Abu al-Qāsim Ja'farī, Imam Hādī's (A.S) deputy and gained his favor. (Tabarī, Vol. 3, p. 1522) Additionally, Mas'ūdī said that Ali b. Mūsā b. Ismā'īl b. Mūsā al-Kādhim joined in the Rey's uprising but the caliph arrested him. Because this person was the grandchild of Ismā'īl b. Mūsā al-Kādhim and served as an…