Bostanai (Hebrew: בוסתאני) was the first exilarch under Arabian rule; he flourished about the middle of the seventh century. The name is Aramaized from the Persian "bustan" or "bostan" (as proper name see Ferdinand Justi, Iranisches Namenbuch, p. 74). Almost the only exilarch of whom anything more than the name is known, he is frequently made the subject of legends.

Bostanai was the son of the exilarch Hananiah. Hai Gaon, in "Sha'are Ẓedeḳ," p. 3a, seems to identify Bostanai with Haninai, and tells that he was given for wife a daughter of the Persian king Chosroes II (died 628), by the calif Omar (died 644). (See Rapoport, in "Bikkure ha-'Ittim," x.83; B. Goldberg, in "Ha-Maggid," xiii.363). Abraham ibn Daud, however, in his "Sefer ha-Ḳabbalah" (Adolphe Neubauer's Medieval Jewish Chronicles, i.64), says that it was the last Sassanid king, Yezdegerd (born 624; died 651-652; see Nöldeke, "Tabari," pp. 397 et seq.), who gave his daughter to Bostanai. But in that case it could have been only Calif Ali (656-661), and not Omar, who thus honored the exilarch (see "Ma'aseh Bet David"). It is known also that Ali gave a friendly reception to the contemporary Gaon Isaac (Sherira II's "Letter," ed. Neubauer, ib. p. 35; Abraham ibn Daud, ib. p. 62); and it is highly probable, therefore, that he honored the exilarch in certain ways as the official representative of the Jews. The office of the exilarch, with its duties and privileges, as it existed for some centuries under the Arabian rule, may be considered to begin with Bostanai.

Read more about Bostanai:  The Dispute Among His Heirs, Legends, Bostanai At The Court of The King, Bostanai in Our Time

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