Shabbetay Ṣevi (Sabbatai Ṣevi, Shabbetay Tzvi, 1626–1676) was born in Izmir (Smyrna) on August 1, 1626, which coincided with the ninth of Av, the fast-day in remembrance of the destruction of the Temple, and also, according to tradition, the day on which the messiah will be born. Shabbetay’s father had moved with his family to Izmir from Greece. The family was apparently Romaniot by origin. Shabbetay had two brothers, Elijah and Joseph.

Izmir, a flourishing city in Hellenistic times (traditionally held to be Homer’s birthplace), was reduced to a small town under the…