During Al-Mutawakkil Isma'il reign and that of his successor, Al-Mahdi Ahmad (1676–1681), the Imamate implemented some of the harshest discriminatory laws (Ar. ghiyar) against the Jews of Yemen, which culminated in the expulsion of all Jews to a hot and arid region in the Tihama coastal plain. The Qasimid state was the strongest Zaydi state to ever exist.