Something happened in the church of San Francesco at Lerici on Tuesday night: one of those unpredictable moments of alchemy in music, which touches the untouchable, no one knows quite why of how – but everyone feels it. It was a musical zenith in the Suoni del Golfo festival that concludes tomorrow night (Friday September 8) with a final concert on Lerici’s lungomare.

The piece programmed for Tuesday night was Berlioz’ Harold En Italie: music inspired by Lord Byron’s poem Childe Harold – hence its connection to the Golfo dei Poeti – by the French composer, another young romantic moved by the landscape and people he encountered around Subiaco, in Lazio, a decade after the poem.

The piece is rarely performed, but good recordings exist, notably under the batons of Leonard Bernstein and Colin Davis – grand in scale. But what the Orchestra Excellence did under festival director Gianluca Marcianò was to lay claim to the piece in a way freshly of their own, with both effervescence and professionalism, for what it is: the reactions of young romantic artists arriving in Italy and falling in love with the place and its people…

… Like Byron did. As did Percy Bysshe Shelley, whose house at Lerici opened to the public on Wednesday night for the first time since he drowned here in 1822. Like Berlioz did. Like I did in the 1970s, and now these young musicians, this week in Liguria, convened by Marcianò in a matter of weeks: 154 were auditioned four months ago, 55 chosen, and the Berlioz piece rehearsed only twice. They come from all over the world: their leader is Venezuelan, the others hail from Russia, Armenia, Egypt… everywhere.

For Suoni del Golfo has been about more than music, as one of the discussion panels in Lerici castle indicated: entitled ‘Music and More’ and hosted by the Vienna-based International Cultural Diversity Organisation, and EMMA For Peace based in Rome – a music project bringing concerts and workshops to refugee and migrant camps in the Middle East, Malta and soon Lampedusa.

For just as Shelley forged with his poetry, here in Lerici, an inspired and inspiring entwinement between morality, culture and politics, so his vision of art intervening in society has been a propulsion of the Suoni di Golfo festival. This is Marcianò’s way: born in Lerici, he began his career in former Yugoslavia, bringing together Serbian, Croatian and Bosniak Muslim musicians to play in Novi Sad and Banja Luka – a Balkan version of Daniel Barenboim’s famous Divan orchestra that combines Palestinian and Israeli musicians.

Then to Armenia and Georgia, in the aftermath of war and tensions between Russia and its former Soviet southern neighbours; and for the last 8 years, Marcianò has directed the music festival at Beit Mery above Beirut – the period that connected the Israeli bombings of 2007 to the present crisis in Syria.

“My life has always brought me to places of conflict”, Marcianò reflects above the peace of the Golfo dei Poeti. “In Bosnia, for instance, I worked with a generation that wants to move on from the hatred, though not to forget, and playing music together is part of that. Banja Luka was lacking an orchestra, and I laid that first stone – the Banja Luka Philharmonic is still there, collaborating with the Sarajevo Philharmonic – it doesn’t solve the problem, but young musicians are reading off the same page, and this is music for a purpose, music with a mission. People come to the festival in Lebanon although their foreign offices say it is too dangerous, and listen. Then they come back and bring other people, without fear to make and hear music; then the education aspect of the project brings music to the refugees – so that the festival becomes a lighthouse, and music a field in which to sow the seeds of the future”.

Marcianò believes that “we need to think that music matters. And musicians should try to understand that they can be part of change for the better. Because music has a power that needs no intermediary element – it addresses the soul directly. Politicians know that, and have tried to use music. But they cannot really touch it. You can imprison a dissident, burn a book or ban a speech – but you can never destroy music. We should not do politics, we have to do music, but with a mission”.

The “great composers”, says Marcianò, “had a message, I believe”. And he makes his point with reference to Giuseppe Verdi, founding father of Italy and master-conduit, in his operas, of a radical romantic liberalism that begat this country and epitomised the best of the 19th Century.  “If you take the poetry of some of Verdi’s operas, like Il Trovatore, it is actually not especially inspiring, even weak. But the libretto is underpinned by the music, which makes it powerful, it gives energy to the words – and it becomes incredible, it moves you, it makes you tremble, it mesmerises you. It brings everything to another level, stays with you after the event and so brings the message”. Verdi, he says, “appealed to Italy as a nation – but in a 19th Century way that called itself nationalism but was not nationalist. His music is about values – values which have no borders, and are universal”.

Ah, Verdi – great Verdi. Music here in Lerici over the past week has included the world premiere of a beautiful piece especially commissioned from British composer Dani Howard, ‘Silver Falls’, on the theme of water, and a sublime performance of Wagner’s Siegfried Idyll in San Francesco – like all the other concerts, packed: a lifeguard in the front row. But it was Tuesday’s concert, starting with Berlioz, that ended with at gale force with Verdi: we did not just hear arias from Nabucco, Aida and Il Trovatore  – we were blown over by them.

Two soloists, soprano Cristina Ferri and baritone Damiano Salerno acted and sung their roles as though on stage, so that every gesture and emotion in their voices sufficient to fill a theatre full of 3,000 people was delivered at point-blank range of a few metres. The inward gaze of Salerno’s eyes seemed to gouge the notes from within him. Never mind Hurricanes Katrina, Harvey and Irma – here was Hurricane Cristina, hurling the music of Leonora’s passion with artful, often wrathful drama, eyes ablaze, décolletage palpitating, voice sublime. Among the audience were the priest flanked by two Sisters, and one wondered whether such overtly profane music had every been sung in this lovely church before – sanguine it certainly was, but not Sanguis Cristi for sure.

It was indeed “mesmerising” and made us tremble, as Marcianò and his festival intended.