People with successful older siblings may recognise the phenomenon: you grow up, leave home, fight your own battles, win a big promotion, even become top in your field, and still find yourself in your sibling’s shadow.

Spare a thought, then, for Edward Bruce, younger brother of Robert the Bruce, the father of Scottish independence. Edward opened a second front against the English by invading Ireland, where he forged a pan-Gaelic alliance, won a string of victories and was crowned high king of Ireland before his death at the Battle of Faughart just outside Dundalk, County Louth, 700 years ago.

Not too shabby a record. But while Robert gets enduring glory – songs and poems, statues and commemorations, a fancy tomb, 3D facial reconstruction, and now gets played by Chris Pine in a Hollywood blockbuster – Edward has to settle for rather humbler recognition: a pub wifi password.

The anniversary of his demise at Faughart on 14 October 1318 passed two weeks ago virtually unnoticed. There were no ceremonies or monuments or even an official wreath to remember the last high king of Ireland. “I’d been aware for years that the anniversary was coming up but it hasn’t been regarded as a priority here,” said Brendan McSherry, heritage officer for Louth county council.

The week of the anniversary a historian, Sean Duffy, gave a talk to the local archaeological and historical society, and a Scottish peer, Andrew Bruce, sent a wreath to Edward’s simple stone grave in a little hillside cemetery. There is talk of placing a commemorate boulder.

The only other acknowledgement of Edward’s existence in the vicinity where he was killed is an inscription on the wall of Michael McCourt’s pub in Dundalk – said to be the site of his coronation in 1315 – and the pub’s wifi password: kingbruce.

Edward Bruce’s grave in Faughart, County Louth, Ireland. Photograph: Rory Carroll/Guardian

It may not compete with the marketing blitz for Outlaw King, the biopic due to hit cinemas next month, but it was better than nothing, said McCourt, as he pulled pints behind the bar.

“He’s not one of the O’Neills or one of them boys that we learn about in history,” he said, alluding to famous Irish chieftains. “Customers know about him to the extent they need to type ‘kingbruce’ to log in to Facebook or whatever. He’s not really known. Ask people here about Edward Bruce and they’ll probably tell you he owes them money.”

Robert’s fame, in contrast, is set for new heights with David Mackenzie’s film. Pine, best known as Captain Kirk in the latest Star Trek films, plays Robert as an inspirational patriot. A scene with full-frontal nudity has won an appreciative fanbase.

One reason the younger brother was forgotten, McCourt suggested, was that unlike Robert he ultimately lost to the English. And his troops alienated many natives. “They were not gratefully received. Edward took what he wanted – pillaged and plundered.”

Michael McCourt, owner of the King Bruce Tavern in Dundalk. Photograph: Rory Carroll/Guardian

Buoyed by his triumph over the English at Bannockburn in 1314, Robert sent his younger brother to Ireland a year later. The idea was to unite local Gaelic chiefs in revolt against English rule, thus draining English manpower and treasure.

All went well at first. Several chiefs declared Edward king and marched under his banner. The joint Scots-Irish force won a string of battles, causing headaches for the English king, Edward II.

But atrocious weather and food shortages crippled the campaign and led to looting. With many natives seeing little difference between Scottish and English invaders some nobles backed the latter, forming a joint Anglo-Irish force.

The allegiances scrambled Ireland’s traditional historical narrative of Scottish arrivals backing the English crown against the natives, said McSherry, the heritage officer. “It undermines the simplicity of the things that we have in our minds.”

The Ulster-Scots Agency, a cross-border body, has placed markers at several sites in Northern Ireland related to the Bruce campaign and hopes to place one at Faughart.

Inscription above Edward Bruce’s grave in Faughart. Photograph: Rory Carroll/Guardian

“It helps people to understand that the cultural reality of Ulster is about the interaction between three distinct peoples, the Irish, the English and the Scots,” said Ian Crozier, the chief executive. “It is the interplay of these three groups down the centuries that have shaped events in Ulster and the society that we know today, but unfortunately the Scots dimension is often overlooked.”

Edward bungled at Faughart – which lies on the border that is currently complicating Brexit - by engaging a larger army without waiting for reinforcements. He was killed and reputedly had parts of his body sent to different parts of Ireland, with the head ending up in London.

Michael McCourt’s pub is also known as the King Bruce Tavern but most patrons this week had not heard of Edward, or had jumbled facts. “I’m just looking him up now,” said Brian Joyce, a bookseller, scanning his phone.

Paddy Larkin, 75, a retired construction worker, thought Edward had a Cain-and-Abel-type relationship with Robert. “Edward came over to get an army to usurp the throne and then his brother came over and battered the shite out of him and and he ended up getting his name on this pub.”