SERERO, SAUL (1566–1655), Moroccan rabbi. Serero was born in *Fez, where his family had taken up residence after the expulsion of the Jews from *Spain in 1492. In 1602 he was appointed a member of the ma'amad of Fez, and in 1621 succeeded Samuel *Abendanan as head of the local bet din. He was also head of a yeshivah, where he had in his possession many manuscript works of the rabbis of Spain, inherited from his parents and grandparents. His reputation as a halakhist spread throughout Morocco, and one of the rabbis of Algiers in a responsum refers to him as "unique in his generation, his word was accepted everywhere as law; no contemporary rabbi could be compared to him."
Most of Serero's works have remained in manuscript, including a homiletical work, a commentary on Proverbs, and kabbalistic works. His most important work is Urim ve-Tummim, a veritable juridical encyclopedia in two parts, the first an alphabetical index of halakhic themes, the second a kind of biographical-bibliographical dictionary, and including a short treatise on weights and measures (Perek ha-Shi'urim ve-ha-Middot).
Fragments of a history of Fez, covering the period 1603–1651, have been translated and published by G. Vajda, Un recueil de textes historiques judéo-marocains (1951).
H. Zafrani, Les Juifs du Maroc (1972).