As in so many European capitals, the Jewish experience in Lisbon mirrors the wider one. Portugal, once a powerhouse that controlled a good chunk of the world through a mighty military and brisk trade, is today mired in debt, thanks to heavy borrowing needed to save the country from red ink (though it is stressed repeatedly that the country is recovering and nowhere near as poor as Greece).

Once home to a thriving Jewish community whose members were seconded to the royal court to serve in a variety of professions, Portugal now has just 700 affiliated Jews, though that number could be as much as 6,000 and even higher if certain genetic traits are factored in (more on that later).

Lisbon’s Jewish history is fascinating, violent and passionate – with all those aspects brought into sharp focus by our guide, Paolo Scheffer, a U.S.-educated art historian whose enthusiasm is infectious and depth of knowledge amazing. He speaks quickly and wastes no words, so pay attention.

We begin in the Praça do Comércio (Commerce Square), a large central plaza that abuts the harbour and is ringed by official-looking buildings. It was here that ships from around the world docked with their exotic cargoes of spices, fabrics and gold.

One of the first things to get out of the way is the word “Marrano,” sometimes used to describe Iberian Jews who were forced to convert to Christianity during the Inquisition. It’s pejorative, Scheffer stressed, and means “pig.” Noted.

Better, in the case of Portugal, to use the term “Cristão Novo,” or “New Christian.” Why?

“Because in Spain, it was ‘convert or leave,’” explains Scheffer, whose mother’s family descended from so-called crypto-Jews. “In Portugal, it was ‘convert or die.’ There was no expulsion.”

Judaism was outlawed in 1498, when Jews comprised as much as a quarter of the whole population, including many Spanish Jews who had arrived under the Edict of Expulsion six years earlier (the faith was not formally legalized until 1822). Very few Jews opted to die but many thousands did flee to places such as Amsterdam, Brazil and the Caribbean, leaving behind all property and, in many cases, even their children, who were left with the church to be raised as Christians (and leaving the king desperate for professionals).

Our next stop is St. Dominic’s church, its blackened interior a vestige of Inquisition processions that began and ended with charred corpses. It was here that in April 1506, a New Christian muttered something sarcastic about a religious relic and was pummelled to death. Spurred by fanatical Dominican monks, the result was a frenzy of blood that overlapped with Passover. The eight-day pogrom killed an unknown number of converted Jews. “It was 4,000 in the first three days,” Scheffer said. “After that, they stopped counting.”

Outside in Rossio Square, a Star of David-shaped plaque, unveiled on the 500th anniversary of the massacre, pays tribute to the “Jewish victims of intolerance and religious fanaticism.” Also in 2006, the Church apologized and asked for forgiveness.

The Inquisition in Portugal was formally established in 1536. Last summer, Portugal’s parliament passed a law granting automatic nationality to descendants of the estimated 400,000 Jews killed, forced to convert or who fled during those dark days.

Sliding effortlessly into the World War II era, Scheffer dismissed suggestions that Portugal had been neutral. “Officially only,” he scoffed. The country, he said, did big business with Nazi Germany, supplying the Third Reich with precious tungsten and being paid in 129 tonnes of untraceable gold. The country never fully addressed the issue. “Portugal still holds Nazi gold,” Scheffer said pointedly.

But Portugal produced two Righteous Among the Nations, the better known being Aristides de Sousa Mendes, who served as the country’s war-time consul-general in Bordeaux, France, and defied orders by issuing 30,000 protective visas to refugees fleeing Germany. As many as 20,000 were given to Jews. Punished by his fascist government and relieved of his duties, he died in poverty in 1954.

Scheffer noted that there is no public monument in the country to Mendes (if you don’t count a small metal medallion dedicated to him in the Parque Metro station, which, Scheffer noted, is about the diameter of grapefruit). For that matter, Lisbon has no Jewish museum, though Scheffer operates a virtual one, at mpjh.org.

There are three synagogues in the country. The Kadoorie Mekor Haim in Porto bills itself as the largest shul in the Iberian peninsula. There’s a 200-member Sephardi congregation in Belmonte, and for the 300 declared Jews of Lisbon, there’s Sinagoga Shaaré Tikvá, which requires notice before visits by foreigners. Scheffer credits Chabad with uniting the community.

Try to get to Lisbon’s Alfama quarter, where a large Jewish community flourished in the Middle Ages. Known as the Judiaria Grande, its labyrinth of narrow cobblestone streets included the Rua da Judiaria. One local church was built atop a synagogue. At the Carmo church in the Chiado quarter, routine digging a few years ago unearthed several centuries-old Jewish tombstones now on display.

The tales gush from Scheffer about famous Jewish doctors, merchants, navigators and masons. The country’s Islamic flavour, still redolent from 500 years of Moorish rule, is clearly spiced with a Jewish one. While Jewish numbers could be as high as 6,000, he cited modern studies showing that up to 20 per cent of all Portuguese – or two million people – have Jewish genetic markers. Between that finding and the food, music and myriad Jewish contributions to society, Judaism “is in our DNA,” he said.