Crypto-Jews: Who Are They, and Where Did They Originate?

A photograph of Spanish Jews from before 1899.

Crypto-Jews, also known as Marrano Jews, originated from the Sephardic Jewish community who resided mostly in the Iberian Peninsula (Spain and Portugal). During the Spanish Inquisition beginning in 1478, the Jews of those countries were forced to convert to Catholicism. While many of the Sephardic Jews fled the countries, others—now identified as Crypto-Jews—were baptized Catholic and followed its practices while practicing Judaism in secret.

Want to learn more about your Crypto-Jewish heritage? Watch a video series about Crypto-Jewish genealogy on for free.

Who Are the Crypto-Jews?

The word “Crypto” means hidden. The group who became identified as Crypto-Jews were Catholic on the outside and Jewish on the inside. They continued with Jewish traditions such as eating kosher food, obeying the Jewish sabbath, lighting of candles, and other traditions. For self-preservation, Crypto-Jews claimed Catholicism. In extreme cases, they may have kept their Jewish identities secret from their children for their safety and the safety of succeeding generations. Over time, others truly converted to Catholicism and never looked back.

Through the centuries some have discovered their Jewish identity from a grandparent or from finding family memorabilia from their Jewish pasts.

The center of the town of Belmonte—a center for Crypto-Judaism
Ken & Nyetta, CC BY 2.0, via Wikimedia Commons

Crypto-Jews History

Many Crypto-Jews immigrated to the Americas and mixed in with local populations. As these families moved about seeking refuge, they were often met with resistance. Some governments passed laws prohibiting their entry. For example, under Spanish rule, Mexico passed pure blood laws (limpieza de sangre or pure blood) like those in Spain. Pure blood laws prohibited “new Christians” from migrating to Mexico. Immigrants, particularly from Spain and Portugal, had to prove that they were “old Christians," meaning they had practiced Christianity for at least 3 generations.

Where Are the Crypto-Jews Now?

Under Spanish influence, Mexico had its own inquisition, and those who had returned back to their Jewish identities were most at risk. For self-preservation, the Crypto-Jews often moved to areas where they were hard to find.

Identifying Crypto-Jewish Roots

Finding family lines for Crypto-Jewish ancestry is much like any other genealogical search. But making the connection that an ancestor who was practicing Catholicism was secretly a Crypto-Jew may require identifying subtle clues. Here are some sources you can use to find your Crypto-Jewish roots.


Among other changes made by Crypto-Jews, they also changed their surnames—many to surnames that ended in “ez,” a Spanish patronymic suffix meaning “son of” or “child of.” The “ez” name ending hints that your Jewish roots probably originated in Spain and Portugal.

Cemetery Headstones

The best sources of clearer information might be found on headstones and cemetery records. Jewish cemeteries are found in many areas, but if there is no Jewish cemetery, there are often Jewish sections in cemeteries. You may also find Jewish headstones intermixed throughout other cemeteries. In any case, headstones may be of traditional Jewish design or include traditional Jewish symbols or designs.

Entrance to a Jewish cemetery.
Aleksandrs Čaičics, CC BY 3.0, via Wikimedia Commons

Language and Architecture

If you are trying to identify whether your ancestor is Crypto-Jewish, take a look at the language and architecture around their hometown. Use of the Ladino language, a derivative of Hebrew with aspects of the old Spanish Castilian language of Spain and Portugal, hints of such origins. Watch for Jewish symbols, such as the Star of David, on or in churches that the ancestor attended, even though they are not Jewish synagogues.

Church Records

Check for your ancestor in church records. Sometimes, Jewish names and vital events were inscribed separately in the back of Catholic or other parish registers.

Family Memorabilia

Looking through family memorabilia might provide clues of your Jewish roots. In a conversation with a Catholic priest, Todd Knowles, deputy chief genealogical officer for Jewish genealogy at FamilySearch, was told that the priest had just become aware of some heirlooms in a trunk his father left to him. The artifacts included yamakas (also known as Kippahs or yarmulkes), stars of David, and other traditional Jewish items. These heirlooms helped him discover his Crypto-Jewish heritage.

Synagogues and Inquisition Records

The most likely place to find Jewish records from many years ago would probably be in synagogue or old inquisition records. These records might be held in the synagogues themselves, but it is more likely that they are no longer held in the synagogues.

Other Sources

About the Author
W. Todd Knowles is a deputy chief genealogical officer at FamilySearch, where he has worked for 22 years. His own journey in family history began by searching for his great-grandfather, a Polish Jew. From those early beginnings, the Knowles Collection was created. This collection now houses the genealogical records of 1.5 million Jews.
About the Author
Diane Sagers was a freelance writer for about 30 years. For 27 of those years, among other things, she wrote 2 to 4 newspaper columns weekly for the Tooele Transcript. She also created and edited a magazine for 27 years, wrote numerous articles for other publications, wrote chapters for several published books, edited documents, and ran a tour company. For the past several years, she has served as a volunteer public relations and marketing writer for FamilySearch and the Family History Library. When she isn't writing, she enjoys spending time with her 6 children, their spouses, and 25 terrific grandchildren, doing genealogy research and teaching others, cooking, sewing, playing piano, gardening, and traveling.