An unknown number of doenmeh descendants -- perhaps thousands -- live in Turkey, and secretly follow their customs and traditions.
Tzvi had seemingly convinced about a third of Europe's Jews that he was the messiah, and his followers began arriving in Turkey at his urging. The sultan was miffed at this invasion and threatened Tzvi, who converted. He lost much of his following at that point, although some adherents adopted Islam for their exterior lives while keeping their faith in Tzvi.
Doenmeh means "turncoat," which is pejorative like "marrano" (pig), a term sometimes used when speaking of Sephardic crypto-Jews. The members of the community, however, call themselves ma'aminim (believers), and in English they are known as Sabbateans. Their commitment to Tzvi didn't die out even after he died in 1676.
There were subsequent messiahs - largely forgotten men like Baruchiah Russo and Jacob Frank - and, as recent scholarship has shown, Sabbateanism greatly influenced the 18th-century emergence of Hasidism. And then there are the doenmeh, who live on until the present day, in secretive communities, at first primarily in Salonika and today almost entirely in present-day Turkey.
Now, however, there is a plan to destroy the building in Izmir (formerly Smyrna) where Tzvi may have lived.
Over the years, most of the doenmeh assimilated into Islam; many more were annihilated during the Holocaust, and still more have, in modern-day Turkey, come to see their background as a curious but largely irrelevant heritage. But even those who did assimilate usually maintained some knowledge of their ancestry, and doenmeh were among the founders of the secular Turkish republic.
The existence of this community is not a well-kept secret in Turkey, but no one speaks about these people who are, according to the article's author, considered traitors by both Muslims and Jews.
The doenmeh who spoke to the Forward about his heritage was unwilling to use his real name.
Is the disintegrating building at 920 Agora Girisi in an old Jewish neighborhood really Tzvi's house? Dr. Cengiz Sisman, an expert on Sabbateanism who received his doctorate from Harvard University, has turned up substantial evidence to that effect.
The article says that Sabbateanism was the first Jewish movement to put women in leadership positions, that Israeli presidents Yitzhak Ben-Zvi and Zalman Shazar were both scholars of Sabbateanism, and that "Theodor Herzl’s opponents labeled him a 'new Sabbetai Tzvi.'"