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LISBON — At first glance, it appears that the future of the Portuguese Jewish community is bleak.

Of the few hundred people who were born Jewish and live in Portugal, most are in the capital city of Lisbon. But they are in a country whose Jewish presence, which was strong at times, goes back to at least the year 300.

Lisbon has its "Judiaria" Street. However, nothing else shows that once, a large synagogue and a thriving Jewish community in Portugal's capital existed.

Most Jews here show little interest in Jewish community affairs. Synagogue attendance is at an all-time low and only a handful of families keep kosher. Three years ago, the Lisbon community welcomed a new rabbi, but he has left.

However, some hope for the Portuguese Jewish community flickers in the distance.

In increasing numbers, members of the Converso population are making formal conversions to Judaism.

This group — also known as "crypto-Jews," New Christians or Marranos, considered a derogatory term — stems from the Spanish and Portuguese inquisitions of the Middle Ages, when thousands of Jews who were forcibly converted to Catholicism secretly continued to practice Judaism.

The private practicing of Jewish customs while outwardly practicing Christianity has been passed down generation to generation.

According to one estimate, thousands of Conversos live in Portugal. The number is difficult to pin down because of the secretive nature of crypto-Judaism.

In Portugal today, families with crypto-Judaism in their background carry out a few Jewish customs, often with a twist, in a clandestine manner. For instance, Shabbat candles might be lit, but the windows are shut while the candles burn inside a closet.

In villages such as Belmonte and Braganca in Portugal's rural northeast, conversions back to Judaism already have occurred.

As these conversions continue, these people may become the new Jewish community of Portugal.

In recent years, increasing numbers of dignitaries, even the former cardinal of Lisbon, have proudly made their crypto-Jewish histories public.