Prince Jonathan Doria Pamphilj and his 1,000-room palace in Rome

Inconspicuously located along the Via del Corso, Rome’s grubby principal artery, the Palazzo Doria Pamphilj is accessed through an unadorned doorway. The visitor enters a porticoed courtyard of lemon trees — the antechamber to one of Italy’s richest private art collections.

The princely Doria Pamphilj family, which has included a pope and a 16th-century admiral, is one of few in the Roman aristocracy to retain its estates, palaces and private treasures.

Prince Jonathan Doria Pamphilj lives above the family “shop”, a gallery of capolavori, including works by Titian, Caravaggio and Raphael, as well as a portrait by Velázquez of Giovanni Battista Pamphilj, who reigned as Pope Innocent X from 1644 to 1655.

Sometimes, when Doria Pamphilj takes friends through the gallery, tourists do a double-take as they recognise his voice from the audio guide. “They realise they are hearing it in stereo, and stop to say ‘hello’,” he says.

The 52-year-old, son of the Princess Orietta and British naval officer Frank Pogson, has the slightly old-fashioned turn of phrase of a Norfolk country gentleman. He refers to “oneself”. It is not easy to imagine him running a Venezuelan beach bar, as he did in the early 1990s before he started running the estate.

His apartment is “a micro-V&A” of eclectic religious artefacts and exotic antiquities. The oldest part of the palace, it came into the family as a dowry when Cardinal Camillo Pamphilj left the priesthood to marry Princess Olimpia Aldobrandini in 1647. Over the next 80 years, the family bought up neighbouring buildings, bolting them together behind a single façade.

Doria Pamphilj occupies a mere 10 of 1,000 rooms in the palace, with his Brazilian partner, Elson Edeno Braga, 47, and their two children, Emily, nine, and Filippo Andrea, eight. The rest have historically been let out to artists, writers or organisations for religious diplomacy such as the Anglican Centre.

He and restaurateur Braga met 20 years ago at the opening of a Brazilian bistro in Rome, and became civil partners in 2006 in Bern, Switzerland. They were one of the earliest gay couples in Italy to use surrogates and their children were the first Brazilian passport holders to have two fathers listed on their birth certificates. The Italian Senate finally voted to legalise gay civil unions last month and the Lower House is expected to follow suit within weeks.

In 2009 Doria Pamphilj’s sister, Princess Gesine, challenged the legal status of his children as heirs to the estate. (The irony was that neither brother nor sister were born into the family as both were adopted from an orphanage in London.) The judge threw out the case. Doria Pamphilj does not want to talk about the dispute, but now has “very little contact” with his sister, who lives in another wing of the palace with her husband and four children.

As Doria Pamphilj points out, he and Braga were able to get around the issue of gay adoption, which is still illegal in Italy, because they hold other citizenships. But he wants everyone to have the same rights.

“It’s such a fundamental thing. The most important institution in Italy is the family. Surely this can only enrich society? It’s a climate of war, like the civil rights movement of the 1960s,” he says.

“Opponents will always pull out photographs of half-naked people at gay pride [events] and say, ‘Do you really want to put your children in their care?’” He says he was incensed by remarks made by designer Domenico Dolce who called children born through surrogacy “synthetic”. “I don’t think his intent was to attack and hurt gay families. But that was the consequence.”

Both a campaigner and fundraiser, Doria Pamphilj works with an HIV foundation, the civil rights group Rainbow Families and recently helped set up a refuge for young lesbian, gay, bisexual, and transgender people who have suffered discrimination. He also founded Edge, a lobbying group for gay professionals. “I’m the only non-professional,” he smiles.

The couple receive “endless” letters from young people who want advice on creating their own “rainbow family”. “They see me, and the role projected on me by society, rather like what’s expected of them in their families. They see that I’m able to break the rules and live my own life and still be here.”

Sitting in his wood-panelled smoking room, next to a fireplace of rare Delft tiles, Doria Pamphilj reflects on his ancestors, who are all around us. His chest puffs out a little when he talks about his family, both past and present. He sees himself not as a black sheep, but as part of a long line of radicals. For the past 200 years, his forebears have exclusively married foreigners. His grandfather Filippo Andrea VI was a firm anti-fascist.

“Some people say, ‘But Jonathan, you have a pope in your family. How can you do and say these things?’ That was 400 years ago. We’ve each made our radical choices. It’s sort of a tradition.”

Doria Pamphilj has resolved that the children should learn the family history from the 100,000 archive documents, some written on goatskin, dating back to the ninth century. He tries — not always successfully — to project a “normal” family life. “We struggle to get up in the morning, scream at the kids because they haven’t done their homework, give them a kiss, do the school run.” Classmates’ parents have mentioned an Audi with a rainbow flag.

He tries not to be too precious with the palace. “We don’t let the kids play football inside but that’s the only rule. It has to be lived in.” The family has been looked after by the same couple for 20 years, except during holidays when they fend for themselves “so the children learn that everybody’s got to pull their weight”. School holidays are spent travelling, between England and Brazil. “We’ve always had ants in our pants. But with children it’s a bit like moving the Saudi royal family around. It’s a lot of suitcases.” The couple are planning to move to Norwich and send the children to an English private school.

On inheriting the palace in 2000 the prince spent two years redecorating, inspired by the eclectic style of the Isabella Stewart Gardner Museum in Boston. The family no longer collects new works so “my only role has been to arrange and move, and contribute my knowledge”, he says. Tin-glazed majolica plates line the walls like portholes. A sea trident sculpture by Bernini, salvaged from a former ancestral villa, dominates a light-filled winter garden.

Papal paraphernalia is plentiful. We sit on Innocent X chairs, used formerly to keep visitors waiting “for a long time, so they would forget their problem”. Maces used in religious processions ornament an ebony tabletop. What looks like an altar is, I’m told, a stand for the tasselled hats of visiting cardinals and bishops. The lids to incense burners, designed by architect Giuseppe Valadier, are attached by wires — some guests have “a fetish” for walking off with things, he explains.

The collection is still throwing up surprises. A series of still lives in the dining room were recently found to be by 17th-century Flemish painter Abraham Brueghel. Under a papal declaration, the estate cannot be divided. Yet the children will not inherit after all. Fearing an increase in Italy’s presently low inheritance taxes, Doria Pamphilj has handed the family’s palace, gallery and vast estates to a trust, stepping back from the day-to-day management.

He has no regrets about not being able to pass on the estate to his children, who will still have an income and the right to live in the palace. “It’s not really a handover anyway. You’re given the keys during your lifetime to live there. Then you’ve got to hand the keys over to the next generation.” Who may continue the tradition of radical choices.

Photographs: Emanuele Camerini