MADRID — When Nuria Guasch's grandfather was on his deathbed, he called her over to tell her something he had never told anyone in his 88 years of life.

"I want you to reflect on your heritage — and think for yourself," Guasch recalls him saying. "And then maybe you'll have the answer to all those questions you were asking."

And then he had a final request: Don't let the hospital's Roman Catholic priest into the room.

As a child growing up in a village near Barcelona, Guasch had wondered about her family's unusual habits, like putting bread and salt on the table every Friday night.

Since most everybody else in Spain was Roman Catholic, she just assumed they were bizarre customs from the Spanish island of Mallorca, where her family came from.

But, as her grandfather had predicted, the answers did come later.

It turned out her grandparents were from among the "Chuetas," or Mallorcans of Jewish origin accused of being Crypto-Jews — or hidden Jews — for centuries after the expulsion of Jews from Spain in 1492.

Many Chuetas married among themselves until the early 20th century because of continued discrimination.

Today, the 49-year-old school principal from Barcelona is ready to reclaim the faith of her forebears.

In a few weeks, she says, she will finalize her conversion to Judaism before a Beit Din, or Jewish court, in Israel.

More than five centuries after the expulsion of Jews by the monarchs of Spain and Portugal, descendants of those who converted to Roman Catholicism to escape the punishment of death increasingly are examining their roots.

During the more than 100 years of pogroms that started in the late 14th century, more than 100,000 Jews are believed to have converted to Christianity.

But many continued practicing Jewish rituals in secret.

In Spanish, the converted Jews were known as Conversos, or "those who converted."

However, the secret Jews were known as Marranos, or "accursed."

Although there is some debate about whether the label Marranos should be considered derogatory, some today prefer Anousim, the Hebrew term for "forced converts."

Their descendants are found not only on the Iberian Peninsula, but also in former Spanish and Portuguese colonies in South and Central America and even in the southwestern United States.

Brazilian-born Rabbi Jacques Cukierkorn of the New Reform Temple in Kansas City, Mo., recalls that as a child, his family had a servant from the rural interior of Brazil.

One Friday night, she saw them kindling Sabbath candles, and she said, "Oh, you light candles too!"

Later, at the Reform movement's Hebrew Union College, he wrote his thesis on the Crypto-Jewish community in Brazil.

"For every Jew in Brazil, there may be potentially a hundred people who have Jewish blood, who are descendants of Marranos," said Cukierkorn, who has helped Marrano communities in Brazil get organized.

Cukierkorn also has written a guidebook to Judaism in Spanish and has traveled to Spain to convert several Jews here, partly because he feels that Jewish communities in Spain — dominated by Sephardi Jews who returned from Morocco in the last 50 years — are not open to Marrano descendants.

"Sephardi Jews ought to be more sensitive to Marranos, but I'm not sure they are," he said.

Reform Jewish leaders are not the only ones reaching out to the Anousim.

The Amishav Institute in Jerusalem was founded in the 1970s by Rabbi Eliyahu Avichail, who embarked on a search for the Ten Lost Tribes and who helped convert the now-famous Crypto-Jews of Belmonte, Portugal.

The organization recently worked with the Bnai Menashe tribe in India — many of whom have since made aliyah — and "lost Jews" in other parts of the world. Now it is turning its efforts back to the Anousim in Spain.

"We, the Jewish people, have a moral and historical obligation to these people," says the director of Amishav, Michael Freund, who was an aide to former Israeli Prime Minister Benjamin Netanyahu.

Freund, who visited Mallorca and Iberia in recent months to talk to descendants, estimates that up to 20,000 people in Mallorca alone are identifiable as Chuetas, while hundreds of thousands of people in the Iberian peninsula and South America can be considered descendants of Anousim.

However, Freund urges caution with his own estimates.

"Not all descendants of Anousim are necessarily aware of their heritage," he says. "And of those that are, not all of them are necessarily interested in returning to Judaism. Some might be happy to remain Catholic while just finding out more about who their ancestors were."

Spaniards in general are becoming increasingly interested in their Jewish history, despite a long tradition of anti-Semitism and official discrimination that lasted through the 1939 to 1975 church-backed dictatorship of Gen. Francisco Franco.

In the old Jewish quarter of Cordoba, near a statue of the great Jewish thinker Maimonides, an old man guards the entrance to the freshly restored synagogue.

He says his surname is Peres Peres, which according to Spanish tradition means that both his father and mother were named Peres. But he adds that even his grandmothers were named Peres, "so actually I'm Peres Peres Peres Peres."

Asked if there are many people in Cordoba who are aware of their Jewish roots, he says: "Half of Cordoba is Jewish!''