It seems fitting to be in Gdansk to meet the new youth orchestra of Eastern Europe.

Poland's medieval ship-building port is where the first bullets of the Second World War were fired and half a century later it became the birthplace of Solidarity. Now the city is crowded with tourists and noisy with beer tents, but reminders of cross-border political history and collective resilience are never far from the surface.

Summer can be hot here. It's mid-morning when I arrive at the Baltic Philhamonic Hall but already temperatures are baking, and members of the I, CULTURE Orchestra loiter in the shade during their coffee break. They've been in residency here for several days, preparing for an international tour that includes their debut at the Edinburgh International Festival. As they stub out their cigarettes and head back inside to rehearse the major work on their programme - Shostakovich's Seventh Symphony - they chatter to each other in Polish, Ukrainian, Russian, English, Azerbaijani, Armenian. A translator cracks multilingual jokes with some of the brass players.

I, CULTURE is the cultural arm of a complex political body. Its musicians, aged between 18 and 28, come from Poland and countries of the Eastern Partnership - a group of former Soviet states comprising Armenia, Azerbaijan, Belarus, Georgia, Moldova and Ukraine. The partnership was established in 2009 to create closer links between these countries and the European Union; the Russian government's response to the initiative has been frosty at best.

The orchestra was founded in 2011, the year that Warsaw held the EU presidency. Funding and administration are provided by Poland's cultural body, the impressive Adam Mickiewicz Institute. And if Polish membership makes up half of the orchestra's numbers, that's because there is better music education provision in Poland than in many of the other countries.

"There are eight conservatories in Poland whereas in Moldova there is just one," says Ewa Bogusz-Moore, the orchestra's spirited general manager. Some players have no orchestral experience - the Ukrainian piccolo player doesn't even own an instrument - while others are already professionals in their home countries. "But we have no quotas on membership because we prioritise artistic integrity," Bogusz-Moore says. "The orchestra has to be good if it's going to succeed, so students must play well to get in, not just come from a certain country."

The conductor of I,CULTURE is 37-year-old Ukrainian Kirill Karabits, a familiar face in the UK as principal conductor of the Bournemouth Symphony Orchestra. He bounces into rehearsal in jeans and trainers and is easygoing with the musicians. He doesn't rush when a flautist has trouble pinning down a tricky rhythm and is happy to wait while a harp player mends a snapped string.

Later, over lunch at a bustling waterfront restaurant, he talks intently about the knack of working with this particular group of young musicians. "The way of treating an Armenian musician is different from the way of treating a Georgian," he says, tucking into a hearty Polish soup served inside a huge loaf of bread. "These musicians have very different backgrounds and different outlooks on the world, but they share an emotional approach to life. They feel strongly about things!"

In many ways Karabits is a role model for these young players. Born in Kiev, he speaks Ukrainian, Russian and English and was educated at home as well as in Germany and Austria. He has a top-flight Western career - he was the first Ukrainian to become chief conductor with a UK orchestra - but says that his roots have become increasingly important to him in recent years.

"A project like this brings me home," he says. "I try to conduct in Ukraine twice a year, though that has been hard recently. To remember who I am and where I come from gives me strength to go and work elsewhere. It's a kind of spiritual food.

"Every time I go to a UK orchestra I have to play their game; when I go to a French orchestra I have to play theirs. I must find a way of preserving my own values, and this project fills me with good energy."

During lunch we talk about the orchestra's various challenges of funding, recruitment and political logistics. Bogusz-Moore says that one of the stickiest issues is around visas: "not a problem for us Poles," she says, "but just try getting a bunch of Georgian musicians into the UK." I ask whether the UK Border Agency has been particularly difficult to work with and she nods.

"It looks likely that our Georgian members won't be coming to Edinburgh. The assumption seems to be that they will come to Scotland and run away - even though they have been rehearsing inside the EU for a week already." Karabits shakes his head. "Doesn't it just prove that the orchestra has meaning?" he says. "That there is work to be done."

Neither Karabits nor the Ukrainian musicians who I met from I, CULTURE wanted to discuss the current crisis in Ukraine, but this year's choice of repertoire has, they say, taken on new significance. Shostakovich wrote his Leningrad Symphony during the Nazi siege on the city; the work has been interpreted alternately as a defiant outcry against military invasion and as an outpouring of Russian patriotism.

"We planned the programme long before things deteriorated in Ukraine," say Bogusz-Moore. "But will we now all stop reading Dostoevsky? This crisis is not about Russian culture. The problem is political." The work's message, says Karabits, is "exactly what we need to hear right now. That the human spirit can stand up against authority. There could be no better moment to perform this work."

The next morning I stop by Gdansk's Academy of Music to meet one the orchestra's woodwind tutors, Samuel Coles, principal flute of the Philharmonia in London. He describes the difficulty of coaching musicians from such varied backgrounds. "I'm not interested in teaching them the nuts and bolts of playing their instruments," he says, "and my role certainly isn't to criticise their teachers. The biggest challenge is finding unity. An orchestra is such a mass of individuals that without a reference point you will have chaos."

Coles says that the students don't generally discuss their politics in the rehearsal room, but that "a political element" is present throughout the project. He tells me about an incident the previous week on the anniversary of the Warsaw Uprising, an occasion traditionally marked in Poland by a minute's silence at 5pm. Just before five, the orchestra happened to be rehearsing the 'invasion' theme from the Shostakovich symphony. They stopped and observed the silence, then played the theme again. "This time they played it with such conviction," says Coles. "No, I don't feel that the politics of the group is heavy, but I do think it's present."

I, CULTURE Orchestra performs at the Usher Hall, Edinburgh, on Sunday