Mr and Mrs Pezzini live in Broughton Street, Edinburgh, in the 1920s.

Signor Pezzini makes Nativity figurines for a living. Mamma keeps house, and there are four children: Lucia is bookish and the narrator of this novel. Emilio is trying to recover from polio. Giulio is a romantic, and Dario, the eldest, is a lusty bully, always of two minds. When Mussolini comes to power in 1922, Dario founds a Fascio, ostensibly a social club for Italian Scots, but supporting the new Italian state and beating the drum for Fascismo. Thanks to the Fascio's funds, the Pezzinis can visit Italy.

Dario and Giulio attend Fascist exercises in Rome, at which almost the entire Scottish delegation faints from the heat. Giulio runs for ice cream, which renders a few of them able to stand when their leader makes a sudden appearance. Taken by surprise, they salute him with dripping wooden ice cream spoons.

The next year, Lucia visits the family village and Rome. She wears a fetching Fascist tunic and marches with a little bow and arrow in a parade before Il Duce (the Pope had drawn the line with Mussolini about girls carrying rifles). Later Mussolini converses with Lucia about Scotland - he seems to know all about Robert Burns and Walter Scott. Someone snaps a photo of her with him; back home she spends precious money on a frame for it.

There's a lot of journeying in The Emperor of Ice-Cream, mostly between Edinburgh and Italy, yet the story is also rooted, even to the point of feeling claustrophobic, in home and family, things held dear in both nations. Dario's fate, as a Fascist demagogue, is, of course, disillusionment, but gets still worse: he's crippled fighting for Il Duce in the Italian campaign in Abyssinia.

Lucia falls in love with a dashing Roman and waits years for him at her desk at the Royal Bank in George Street, where she becomes savvy enough about money to help her brother Giulio realize his dream, which is to open the most wonderful ice cream shop in Scotland: the Ice Palace.

Situated in Annandale Street, just a few steps from what was thought of, and perhaps still is, the Italian heart of Edinburgh, the Ice Palace dazzles the people of Broughton and beyond. For Italians it's a more familial place to meet than the male-only bars of the day, and the Fascio is rapidly becoming a contentious venue.

Indeed Giulio planned his shop to be just this, as he publicly rejects the Fascio and Fascism too (we later learn another reason why he was destined not to fit in to the rise of Aryanism).

There is much here of the twentieth-century Italian experience in Scotland. There is also a lot about ice cream, a bit like the way in which Patrick Süskind's novel Perfume linked political upheaval and the art of fragrance: what flavours tickled the 1930s palate, and the great dynasties of ices: Nardini, Luca.

Your reviewer is, sadly, lactose intolerant, but he awoke in the night thinking of the exotic flavours and combinations concocted by Giulio after he visits the ultimate masters of his art, La Scimmia of Naples and Giolitti's in Rome: "Bitter Cherry and Blood Orange so tart it sets the roof your mouth on fire". Cinnamon sorbet! More than just a meeting place, the Ice Palace is the hub of several romances - love is the real subject of the book.

Earthy Aunt Paola, so impressed by Giulio's success and so depressed by Scottish cooking, also opens a shop on Annandale Street (which by now is referred to by locals as the 'Via Pezzini'): Paola's Neapolitan Fry. Just in case you thought fish and chips (and deep-fried zucchini) weren't going to get a mention.

When Mussolini abruptly signed his pact with Hitler, the British government started rounding up Italians, mostly male. "Collar the lot," Churchill said. There were vigilante outrages too, and Edinburgh was no exception: it took Giulio and Lucia almost two years of scraping and sacrifice to make the Ice Palace come true, and at the hands of frightened bigots it is ruined in one terribly sad, violent moment. "Who knows what will be released upon the children of us Italians?" asks Giulio.

It's often said that there is a fundamental sadness to Italian life. Perhaps that is another trait shared by the two countries of this story.

As Lucia warms to her narrative, the prose, generally a little cautious and overly measured, can burst into affecting moments: The Emperor of Ice-Cream gets deeper and scarier as it progresses. Things don't go well for the Pezzinis - in Edinburgh and in Italy there is primitive violence, horror and death.

It's a big family and a lot happens to them, all because of nationalism, love and gelato.