Zaydism is often depicted as the variant of Shī‘ism most similar to Sunnī Islam. Popular and academic works emphasize the apparent overlap between Zaydī and Sunnī (Shāfi‘ī) legal methodology. There is also a general assumption that the Zaydīs accept the legitimacy of the caliphal reigns of Abū Bakr and ‘Umar in contrast to the more intransigent and hostile attitude of the Ismā‘īlīs and the Twelvers. In fact, the Zaydīs are often identified as Shī‘ī exclusively on the basis of their belief in ‘Alī's right to the succession after the Prophet's death. Such characterizations obfuscate one of the central dynamics in Zaydī history – namely, the Zaydī community's oscillation between Sunnī and Shī‘ī positions in matters of theology and law. A proper understanding of Zaydī Shī‘ism in its “classical” form (referred to below as “Hādawī”) requires the examination of two important transformations: (i) an initial shift from a predominantly (proto-)Sunnī to a Shī‘ī orientation in the ninth century and (ii) a subsequent “Sunnification” fueled by political and religious pressures beginning as early as the fifteenth and sixteenth centuries.

The Initial Oscillation: The Emergence of Hādawī Zaydism

As mentioned in Chapter 4, Zayd b. ‘Alī was quite moderate in his views on the Prophet's succession, refusing to condemn the first two caliphs as usurpers and extending the scope of legitimate religious authority to non-‘Alid scholars (e.g., his teacher Wāṣil b. ‘Aṭā’). This stance was opposed by many Shī‘ī groups, who denounced the early caliphs and restricted religious authority to the family of the Prophet. According to the heresiographers, Zaydism resulted from the merging of two varieties of Shī‘a known as the Batrīs and the Jārūdīs. The Batrīs held positions similar to those of Zayd, whereas the Jārūdīs embraced the more activist agenda of other Shī‘ī groups. By the end of the ninth century, the Batrīs disintegrated and were absorbed into an emerging Sunnism, and the Jārūdīs came to dominate Zaydism.