YOU don't have to be Simon Schama or Lucy Worsley to know there were no portaloos at the Battle of Bannockburn in 1314.

There will be portaloos when Norwegian Malin Heen-Allen and her husband Charlie Allen set up camp for their 21st-century recreation of the battle this summer - but they will be one of very few concessions to modern comforts in what promises to be as faithful a recreation of life and war in the 14th century as is possible today.

Heen-Allen calls what she and Allen do "living history". Others might call it dressing up in scratchy, woollen clothes and running round a field brandishing a claymore or a two-headed axe. But whatever your view of the pastime, it has its fans and they all have an important role to play in the National Trust for Scotland's epic Bannockburn Live festival.

"It's going to be a big celebration weekend, the anniversary of the battle done as a Scottish showcase with Scottish music, food and a celebration of Scotland's natural landscape," says Heen-Allen. "It will be like a mini Scotland, set up at Bannockburn."

The new Bannockburn visitor centre is expected to open in March, but the festival takes place over the last three days in June and marks the 700th anniversary of a pivotal Scottish victory in the Wars of Independence. Fought over two days on June 23 and 24, 1314, it saw Robert Bruce's army of Scots beat the English under Edward II and, as the song says, send them homeward to think again.

Just as importantly, the victory also gave rise to the Declaration of Arbroath, which asserted Scotland's right to be an independent nation in ringing phrases which have carried down the centuries: "It is in truth not for glory, nor riches, nor honours that we are fighting, but for freedom - for that alone, which no honest man gives up but with life itself."

Heen-Allen's contribution to the event, which is expected to draw some 45,000 visitors, comes through her position as manager of the Clanranald Trust, a charity established in 1995 by Allen with the aim of promoting awareness of Scottish culture and heritage. It also operates Duncarron, a recreation of a palisaded mediaeval village situated near Stirling which has been used to film an upcoming Neil Oliver-fronted BBC Scotland documentary about Bannockburn. Allen and other members of the Trust have also featured as extras in films as varied as superhero movie Thor and Valhalla Rising, Nicolas Winding Refn's Viking bloodfest set 300 years before Bannockburn.

Given that resource and their combined experience in living history events, Heen-Allen and Allen will be co-­ordinating a recreation of the battle featuring around 300 participants - three shows a day, come rain or shine - and building a mediaeval camp to replicate the ones which the rival English and Scottish armies would have occupied in the days leading up to the battle. Around 150 people will be stationed there, made up of volunteers from the living history scene.

"Most of the re-enacters will be sleeping in the living history camp in canvas tents, but we will have sleeping bags too," Heen-Allen says. "But a lot of re-enactment groups are so well-equipped that they bring along wooden beds, straw mattresses and sheepskin bedding, and some of these tents will be open to the public so people can see what a bed would have looked like in 1314.

"We want people to come up and say, 'I was in Edward II's tent today and his bed was amazing.' It's the kind of thing you'd never forget if you're six years old. We want to create an atmosphere where we can say, 'If you were here 700 years ago, this is very much what it would have looked like'."

There will also be demonstrations of how the army was fed and the opportunity to taste some of the things the troops would have eaten as Heen-Allen and her colleagues bake bread and cook food in special kitchens they will set up.

Then, of course, comes the fighting as the opposing sides take to the field in a battle whose outcome we already know. And that's men's work, right? Wrong, she says - there may well have been women among the Scottish fighters.

"In Scotland, there weren't that many wealthy landowners or organised soldiers, so on the Scottish side, especially in the schiltrons [the Scots' pike formations], who's to say there wasn't a woman or two - or maybe 100 or more? Once you're padded up and helmeted with a 12ft pike in your hand in a cluster of 100 other people, who's going to know? So I'm pretty sure there will be some women involved on the field this summer."

Dress is as authentic as possible too, which for Heen-Allen means layers of skirts: "I will be in full mediaeval female kitchen-helper costume. That includes linen, cotton, some silk and a lot of wool, which sounds hotter than it has to be because some of the wools are quite fine.

"They called the women who travelled with the army 'sparewives' and they would look slightly different - all the dresses were much shorter because there was a lot of running and walking and climbing involved in setting up camp. Which brings us full circle to the question of women on the battlefield - I think you would be hard-pushed to tell men and women apart there, because men's tunics were worn long and the sparewives' dresses were short and they wore leg wraps round their boots."

There is also a cloak, she adds, for sleeping in and for protection from the rain. Ah yes, the rain. "We have done some weekends at Duncarron where it has been raining non-stop and up there we have no modern buildings. But when you're wet, you're wet. I have been so wet that your fingers go funny, like when you're a kid and you're in the bath for too long."

Talking of children, Malin and Charlie have five, ranging in age from seven to 21. So what do they think of how mum and dad make a living?

"Someone asked our 13-year old if she was ever embarrassed by us - especially by her dad, because people see him on TV, and he's always some barbarian beating people up or chasing Thor down a corridor or whatever," says Heen-Allen. "She said, 'You know what? They have surpassed how embarrassing you can get as a parent … and now they're bordering on cool!'."

www.bannockburnlive.com