Julie Fowlis would love to have struck gold for her appearance at Bannockburn Live this weekend.

The Gaelic singer, who has taken songs from her homeland of North Uist across the world and appeared before a television audience estimated at 500 million when she sang at the closing ceremony of the Ryder Cup in 2012, would have liked to have a song in her repertoire that gave the Bannockburn crowd a connection between her island home and the battle itself.

"I know plenty of Gaelic songs that tell of men going off to war and leaving sweethearts and families behind, and there are songs in the Gaelic tradition that are allegedly old enough to date back to the time of Bannockburn," she says. "But I haven't uncovered one from North Uist that makes that connection, although that's not to say that there wasn't such a song. It's a fascinating thing about traditional music, how it's always been a powerful medium for preserving our history and passing it on."

One particular song in the Gaelic repertoire that captures the mood of a man going off to battle and his desire to be home with his lover has proved especially popular among Gaels, says Fowlis, having been recorded by artists as diverse as Calum Kennedy, Donnie Munro and Capercaillie, as well as Fowlis herself.

"An Eala Bhàn, the White Swan, was composed by Dòmhnall Ruadh Chorùna at the time of the Battle of the Somme and it has really powerful imagery of this woman he's left at home and how he's praying that he'll get back to her," she says. "It's one of many beautiful songs in the Gaelic tradition that have been written by men while they were away, often fighting for a cause that was far-removed from their real lives. I find these songs quite difficult to sing, to be honest, because they can be so emotional. But it maybe says something about the Gaels and their history that such a song is one of the ones they relate to most."

Although she was keen on history as a subject at school, Fowlis has learned more about the past through her own research, some of it as part of formal education - she took a Master's degree in Gaelic Culture and served as an Artist in Residence with the digital archive project Tobar an Dualchais - some of it to discover the background of the songs she sings and the stories behind them. Her knowledge of North Uist's history, she says for example, has almost entirely been gained through learning songs.

"I think it's really important if you're going to perform these songs and be true to them that you find out the background to them," she says. "Looking back, I could have done with learning more about Scottish history at school. I mean, I'm not sure we should be looking at Bannockburn in isolation, although I understand why it's taking centre-stage right now on its anniversary. I'd like to have learned more about a whole series of events and understood why they happened and how they've affected Scotland because just in terms of understanding what was going on at the time a song was written, it can be really satisfying to have that knowledge behind you so that you think about it as more than words and music. It's been written for a reason."

It's been one of the triumphs of a career that has seen Fowlis being hired to produce and record music for a Hollywood film, the animated adventure movie Brave, that the songs she sings largely come from an island community that wouldn't previously have entered the music, let alone the film, business's consciousness.

One of the events she credits for making this possible is one that she's returning to later this summer, Cambridge Folk Festival, as part of the Creative Scotland-funded Scottish showcase which includes Aly Bain and Phil Cunningham, the Peatbog Faeries, fiddler John McCusker in his trio with Michael McGoldrick and John Doyle, the young Lewis singer and harp player Mischa MacPherson, and young musicians from Feis Rois, for whom Fowlis once worked as music development officer.

"Cambridge has a big anniversary this year, too, its 50th," she says, "and I'm really grateful to the organiser, Eddie Barcan and his team because he gave us opportunities to perform very early on. There weren't many other promoters outside of Scotland at the time who were willing to give programme space to someone singing entirely material in Gaelic, let alone songs almost exclusively from North Uist."

As well as being welcoming to Scottish musicians over the years, Cambridge also scores highly with Fowlis for atmosphere. It's the sort of event where musicians are encouraged to congregate and socialise, rather than being ferried in to do their spot and then ferried out again.

Downscale in size, if not in anticipation levels, from Cambridge but a success for similar reasons is an event that Fowlis will be appearing at this year for the first time, Tiree Music Festival.

"Tiree's one of my favourite places, I've been to the island lots of times and I think the festival's success - it's been sold out for ages - is down to having lovely people organising it, good programming and a fantastic location," she says of the event where she's been invited to appear as the opening attraction. "It's hard to think of a more appealing place to have a festival, really, and I think that because it has musicians at the helm who know what it takes to entice other musicians over to the island and keep them happy once they're there, that vibe spreads to the audience. Of course, it's a captive audience - and cast - because once you're out there, you're out there."

Since her involvement in Brave, Fowlis has been busy recording and then promoting her fourth album, Gach sgeul (Every Story), which was released earlier this year and although she has no firm plans for further film work, it's something that comes up in conversation from time to time and would certainly be of interest to her. The call to work on Brave came out of the blue and as she says, the music business is all about making connections - you just never know where they're going to lead.

"It seems like a long time ago that we were having these phone calls and emails from California but people still come up after gigs and talk about it," she says. "It was great to be involved and you never know what effect doing that sort of thing can have because as well as wee lassies who come up and tell you that they want to be Merida, you get people who had no previous experience of Gaelic music saying that Brave introduced them to something that's become quite important to them and that they've gone on to discover other Gaelic singers, which is great."

She's less comfortable with the role of ambassador for Gaelic music that she's acquired and never thinks of herself in such terms, and while she would always be honoured to be asked to sing at events such as the Ryder Cup and international football matches, she's more likely to be the one who's star-struck on these occasions.

"We got to meet Paul Lawrie and his wife last year," she says, "and we were so chuffed because Paul's a champion golfer and we watch him on television. But they told us that they'd watched the Ryder Cup closing ceremony on YouTube lots of times and that was really nice to know. You forget that people like that have lives outside of what makes them famous and that they do everyday things like listen to music and watch their favourite YouTube clips."

Julie Fowlis appears at Bannockburn Live tomorrow, Tiree Music Festival on July 18 and at Cambridge Folk Festival on August 3, www.juliefowlis.com