I recently interviewed Louis Mendola in Palermo, having first met him there four years earlier, in 2015. This spring, Sicily was experiencing unseasonably cool weather. None the less, the interview took place outdoors, in Piazza Bologni, a few steps from Mendola's cluttered office.

Interviewer: Tell me something about this square.

Mr Mendola: Over near the street, which was once a Phoenician road, you can see a statue of Charles V, the Holy Roman Emperor. This piazza is named for the Bologna family, which owned some of these buildings into the seventeenth century. When the Bolognas fell on hard times they had to sell most of their land. Here's a useless fact: One of my ancestors bought a feudal estate from them. My grandfather, Luigi, still had a piece of it three centuries later, in the late fifties. [With this, Lou shows me a pic on his iphone.]

Interviewer: Beautiful. Where is this place?

Mr Mendola: In the Sicanian Mountains, along both sides of the Platani River, the Halykos. With the Philinus Treaty, in 306 BC, this river separated the territories of the Carthaginians and Greeks.

Interviewer: Speaking of Carthaginians and Greeks, I've read the [recent] books you sent me. They're all good but it's still The Peoples of Sicily that holds my interest.

Mr Mendola: You're not alone. That's the book that sells the most from year to year. It went to press in 2014 and still attracts interest.

Interviewer: Why is that, do you suppose?

Mr Mendola: The message, the implicit message. The book talks about how – at least for a while – people of different cultures and faiths lived here without killing each other. We can learn something from that.

Interviewer: I see a great number of new immigrants, particularly in this part of the city.

Mr Mendola: It's a phenomenon of the last twenty years. Before that, the last major influx was the Albanian refugees around 1500, and the Jews had been expelled – or in some cases forcibly converted – in 1493. And two centuries before that, the Muslims were converted to Christianity.

Interviewer: How many Jews and Muslims were there in Sicily in the Middle Ages?

Mr Mendola: As far as we can tell, when the Normans arrived, in 1061, probably about forty-five percent of the Sicilians were Muslims, of Arab descent, and maybe six percent were Jewish.

Interviewer: And the rest were Christians?

Mr Mendola: Yes. What we would now call Greek Orthodox.

Interviewer: Your book on genealogy talks about research using DNA. Has that changed opinions about this history?

Mr Mendola: The reality is that phylogeography is tricky with Mediterranean populations. There's a fair amount of crossover. There's also genetic drift, so what you test today isn't exactly what was here in the eleventh century. But certain haplogroups are still present, and they confirm what the historical record – the written record – tells us. So I would say that, in the case of Sicily, there haven't been any great revelations from DNA. It pretty much confirms what we already knew – that we, the Sicilians, are the Greeks, Arabs, Normans, Swabians and Jews.

Interviewer: And you were the first Sicilian historian to integrate this genetic record into your work?

Mr Mendola: One of the first. At one point I uploaded a short paper about it because I was getting so many questions about the subject from other historians and reading strange queries about how Sicily's Arabs "disappeared" when most actually converted.

Interviewer: The DNA research is from published studies?

Mr Mendola: Yes. That's what I consulted at first. Then I found that the database at Family Tree DNA – which is always growing – was a larger sampling, and in some ways a better one.

Interviewer: You've been knighted by the Order of Malta, which is quite influential in some countries. What's your title?

Mr Mendola: I don't use one.

Interviewer: But we have those titles in Britain, where people are knighted by the Queen. Here in Italy aren't you a commendatore, or a cavaliere, something like that?

Mr Mendola: Yes. And maybe I'll start using one of those titles when I'm seventy or eighty. The Order of Malta, which was founded nine centuries ago, knighted me to recognise my scholarship in the field of medieval history. That's very satisfying. When I wear the lapel pin – the rosette – in Vatican City, it gets me a salute from the Swiss Guards posted at the Porta Sant'Anna, the entrance to the courtyard that leads to the archive and library.

Interviewer: Let's talk about that. When I was here last, we spoke about your experiences in the field, and how you were one of the few scholars granted unrestricted access to the Vatican archive back in the early nineties. You were close to some highly-placed cardinals. What's your connection to that whole [Catholic] environment?

Mr Mendola: It's not the philosophical connection that outsiders seem to imagine, as if there were some kind of esoteric cabal. Even if nobody really thinks about it very much, medievalists fall into certain environments, or pseudo-environments, based on their educational backgrounds, and maybe their social backgrounds too. There are what might be called orbits or niches. This happens to be mine, not really by choice but because of circumstance.

Interviewer: That's interesting. Could you elaborate on it?

Mr Mendola: It's subtle. I'm not suggesting an overbearing set of rules or anything like that, or a subculture. But there's what might be called the Oxbridge nexus, the Ivy League nexus, and so on. "Influence" might be a better word because you don't have to go to Cambridge to have that state of mind. Then there's the Vatican nexus, which embraces, I'd say, most of the scholars in places like Germany and Spain as well as Italy. It doesn't really isolate anybody. Scholars interrelate with each other at conferences and by pursuing specific studies together. What I'm describing influences mentalities but it's not really about nationalities or religions. A Catholic might go to Oxford and a Protestant might study at Georgetown. But certain areas of study are dominated by people from certain countries.

Interviewer: In what way?

Mr Mendola. Well, geographical details are best left to people who live in the place and really know it, because Google Maps can tell you only so much. I recall a study on an important chronicle of events in Palermo during the twelfth century where the author, a well-known professor of history who lives outside Italy, got the location of a church wrong. What's left of it is behind that building across the street. [Lou points to a restructured palazzo.] Another area is translations from Latin into English, done by native speakers. Most of the best Latinists, both classic and medieval, are scholars in the Vatican circle, people from Italy or Spain. I've seen passages of Latin text – from things like medieval chronicles – rendered strangely by some of the best Anglophone Latinists, but the Italians never seem to miss. It's the similarity of the languages and because Italian has expressions, figures of speech, that come directly from Latin that are still in use after a thousand years. Many of those expressions no longer exist in English.

Interviewer: Can you give me an example?

Mr Mendola. I'd rather not mention a text, because then I'd be identifying a specific scholar's translation. I don't like to shoot down the work of other historians. But a medieval expression still in use would be "faster than you can cook an egg."

Interviewer: Are there areas besides language where you see these differences?

Mr Mendola. People in the Vatican nexus can be expected to understand the Catholic church and the papacy well. That's important in medieval studies. What's missing in all the circles I've mentioned is a keen understanding of the Eastern Orthodox church, which is important for southern Italy during our Norman period. I'd say that the eastern Europeans have their own scholarly circle. That's important in the Byzantine part of our history.

Interviewer: "Our history" meaning the history of southern Italy?

Mr Mendola. Yes. That's another aspect of historiography, informal "factions" I refer to as "natives" and "visitors." For most scholars from outside Italy, this country is what I call a "pet culture."

Interviewer: "Pet culture." What does that mean?

Mr Mendola. It's another social side of scholarship. Let me explain. I've studied Russian and the history of Russia. But I'm not Russian, so for me Russia is a "pet culture." That makes me a "visitor," both literally and figuratively. It's my interest but not my personal heritage, my identity. A comparison would be a white professor teaching Japanese or black studies, or a man teaching women's studies. The exception is somebody like Sir Harold Acton, who was raised in Italy even though his roots were English. But then some work overlaps cultures. One of my heraldic papers from the nineties considers the use of the "English" lion and "French" fleur de lis in Sicily before 1160. Heraldry was always international, going back to the days of the Crusades. In spoken conversation, a "visitor" refers to the Sicilians. I sometimes use words like we and us. It's personal.

Interviewer: Besides curiosity and identity, what is your focus, the thing that encourages you?

Mr Mendola: The response of readers encourages me. There are some aspects of my work that people find inspiring. It's not about the applause. But I have to admit that getting a standing ovation from a group of university students following a talk about multiculturalism in medieval Sicily is great for the ego. I've often said that most of my work is just filling in the gaps. A fair number of books have been published in English about certain subjects but not others. I work on the others.

Interviewer: Like the translations of the chronicles?

Mr Mendola: That's an obvious example, yes.

Interviewer: What kind of an impact have the translations had?

Mr Mendola: The Rebellion has actual fans. I got emails from people who usually enjoyed other languages and genres, like Norse chronicles, who were thrilled to see something in Sicilian. For two weeks in May 2016 it was at the top of Amazon's new releases in medieval literature. The Jamsilla Chronicle has also done well. When the publisher got requests for advance copies of it from about a dozen students – mostly in England and the United States but also in Germany – I paid for the books and shipping. It seemed ignoble to do otherwise. I can see how a publisher is reluctant to do that. He's running a business. But these junior scholars writing papers and theses needed this work. It's my feeling that writing books is about more than making money.

Interviewer: Aren't there other scholars here in Italy working in these areas?

Mr Mendola: Yes, but the greatest obstacle is the language. I've never met a historian from this country – even one who's worked in Britain – whose command of English was sufficient to write an entire monograph in English on his own. And academic publishers outside Italy don't like to spend money to translate a ninety-thousand word monograph from Italian into English. Most of the time, they'd rather pay an Anglophone to write something similar in English.

Interviewer: How is the scholarship outside Italy?

Mr Mendola: Some Italianists in the English-speaking countries are very good. A few British professors of Italian history entertain eccentric opinions. I know of one who wrote that there is no Mafia, and another – a medievalist – who traced that organisation to Muslim-Arab attitudes present here, in Palermo, at the time of William I of Sicily. Both were mistaken but I can't be getting into debates over that kind of thing. What they write, or tell their students, is none of my concern.

Interviewer: I see glowing reviews of your books on Amazon. Has there been any negative feedback?

Mr Mendola: A few snitty comments. But like Frank Sinatra used to sing, "too few to mention."

Interviewer: It's hard to imagine anybody being critical of your books.

Mr Mendola: Well, some criticism is normal. No book pleases everybody. I think I'm entitled to a few critics!

Interviewer: Who are they?

Mr Mendola: The negative reactions seem to come from two obscure corners of the readership. I get hate mail about The Peoples of Sicily because I'm seen as "the multicultural guy" and there are some readers – like Sicilian descendants in America – who are "offended" by Islam or the fact that they have some Arab or African ancestry. That's plain racism. Then there are professors resentful that I got a book contract to write something they wanted to write. That seems to me like "sour grapes."

Interviewer: How do you respond?

Mr Mendola: I don't respond to racists and hecklers.

Interviewer: But if you did?

Mr Mendola: To the racists, look at the genetic record – the haplogroups – and the Arab contributions to Sicilian culture. You like cannoli? Thank the Arabs for bringing sugar cane to Sicily. You like spaghetti? It was invented by the Arabs in Sicily. The jealous academics are usually not Italians but foreigners who've "adopted" Italy as their "pet culture." My response to them would be that the chronicles sat in libraries for centuries until I translated them, so go do the work yourself if you don't want to see somebody else do it. And I'd remind both groups that we have freedom of the press now, so it's a silly waste of time to try to censor a historian.

Interviewer: Has anybody ever attacked you like this face-to-face?

Mr Mendola: No. It's always by email or someplace online, never in person. Which is good, because I believe that in some cases there may be identity issues involved with those kinds of reactions. But I really don't want to paint every critic with the same brush.

Interviewer: Do you ever meet your readers?

Mr Mendola: Yes, but they're usually the normal ones. I've done book signings. I give lectures three or four times a year. Usually to groups of university students visiting Sicily. Last year the largest group was YPO. Almost a hundred people, mostly over forty.

Interviewer: So you do come in from the rain on occasion. What happened to the recluse lifting weights at the gym?

Mr Mendola: I still lift weights but I've never been a recluse. There's no isolation. I'm on Academia.Edu but I'm not going to attend a conference in England just to hear somebody present a paper all about the icon of Thomas Becket at Monreale, something that's already been studied to death. I'm not invisible. Any colleague who wants to find me can look me up when they come to Sicily. I imagine they would visit the place they're writing about. Sometimes people who've read one or two of my books try to find me when they come to Palermo. The point is that I don't do cocktail parties very well, and I try to avoid certain obnoxious colleagues. I don't suffer fools gladly. At all.

Interviewer: What is it about them that gets on your wick?

Mr Mendola: The rivalries, the turf wars, the cat-fighting, the pedantic attitudes. But it's not just my personal experience with the eccentrics and obsessives. Sites like Rate My Professors and The Chronicle of Higher Education are full of horror stories about bizarre incidents in academia. [Lou takes out his phone and shows me three extremely negative reviews written by students about a certain professor of medieval history.]

Interviewer: No wonder all of your books are dedicated to the dead!

Mr Mendola: To people I miss. Cyril Toumanoff and Steven Runciman were great historians. Each of the others was great in his own way.

Interviewer: What did Toumanoff and Runciman focus on?

Mr Mendola: The Byzantine East, the Crusades. Toumanoff was Georgian and Russian, so his interest in that region was natural. Runciman was English to the core. He just had a profound interest in the eastern Mediterranean, and Sicily.

Interviewer: You were their student?

Mr Mendola: Not formally. With Toumanoff I did some research involving the history of the Knights of Malta. Runciman encouraged me to write about Sicily. Toumanoff was dogmatic; Runciman was just complicated. But I knew them when they were older. I imagine they were different in middle age.

Interviewer: Dogmatism and complexity come with the territory, don't they?

Mr Mendola: Yes and no. These two were true gentlemen, not just because they were aristocrats but because of their natures. They were decent human beings. The loss of that generation of historians was a loss for all of us.

Interviewer: When were they born?

Mr Mendola: Over a century ago. Before the First World War.

Interviewer: It isn't often that one hears this kind of praise. Would you say that your respect for them is part of your respect for the past?

Mr Mendola: Absolutely, because each historian is a link in a chain. Great men are never forgotten, or shouldn't be.

Interviewer: Which historians [working today] do you admire?

Mr Mendola: A few who come to mind are David Abulafia, Leonard Chiarelli and Hiroshi Takayama, who write about medieval Sicily, and my friend Charles Beauclerk, a biographer. In the last five or six years, a few women have made their mark in writing about Sicilian medieval history. I'm thinking of Dawn Marie Hayes and Jacqueline Alio – both Sicilians – and Sarah Davis-Secord. Google them. They are an asset to the field. Good historians and good people.