After 1002, the Zaidi imamate in highland Yemen was contested between various claimants. A Caspian Zaidi leader in Persia, Abu Talib Yahya, is sometimes formally counted as imam in the period 1020–1033 in Zaydiyyah historiography. Meanwhile, the brother of the old imam al-Mahdi al-Husayn, Ja'far, ruled the Zaidi centre Sa'dah as emir for periods. In 1027 a new pretender of obscure origins appeared and claimed the imamate. He proclaimed himself under the title al-Mu'id li-Din Illah (he who brings people back to God). He actually managed to establish his authority in the important city San'a. Nevertheless, he was killed by opponents already in 1030.
- H.C. Kay, Yaman; Its Early Medieval History. London 1892, p. 229.