Archaeologists searching for the remains of Red Hugh O'Donnell, one of Ireland's most loved historical heroes, have begun digging up the streets of Valladolid in Spain.
Historian Hiram Morgan, a UCC academic, said O'Donnell's skeleton should be easily identifiable - because he had no big toes.
O'Donnell, who was the mastermind of the Nine- Year War from 1593 to 1603, suffered frostbite while hiding in the Wicklow mountains following a daring escape from Dublin Castle.
Along with his father-in-law Hugh O'Neill, Earl of Tyrone, Red Hugh led arguably one of Ireland's most successful rebellions against the English.
Red Hugh, an Irish nobleman, of the Donegal O'Donnell dynasty, died in Spain in 1602 while trying to secure the support of the Spanish for a further invasion in Ireland against their shared enemy, England.
After suffering defeat during the Siege of Kinsale, he travelled to Spain to seek further support from King Philip III.
While there, aged just 29, he contracted an infection, or according to others, he was poisoned by British spy James Blake, a merchant sailor from Galway.
Blake claimed he had assassinated Red Hugh on behalf of the Governor of Munster, George Carew.
But historian Mr Morgan said it was generally considered Blake claimed this just to "get some kind of benefit from Red Hugh's death".
"He claimed he poisoned him, but there is no proof of that really. The Spanish records seem to say Red Hugh had a fever for about a week and then died.
"The Spaniards didn't think there was anything untoward."
Red Hugh led a colourful life, and his backstory has fascinated historians for centuries.
Mr Morgan said the interest in Red Hugh was not surprising - he was a classic hero.
"He was one of these Irish heroes who tried and very nearly succeeded, and he also has this great backstory.
"He was captured by the British and managed to escape."
At the time, a common tactic among the English was to take the sons of Irish nobles as prisoners and hold them in Dublin Castle.
They used the threat of execution to keep the nobles in line.
The English used a ship loaded with beer and wine as a ruse to capture Red Hugh.
They sailed it up the coast to Lough Swilly, putting it in to harbour near Rathmullan.
They pretended to be merchants selling the wine and beer and managed to draw the young Red Hugh onboard.
However, they captured him and threw him in the hold before immediately setting sail.
The O'Donnells had no boats to pursue his captors and could only watch as the ship sailed back around the coast to Dublin, where Red Hugh was imprisoned.
Mr Morgan explained: "His father-in-law Hugh O'Neill and others arranged his escape, and that was when he had to hide in the mountains.
"When he got back to Donegal about a month later, they had to amputate his big toes.
"If they find his body in Spain, they will be able to identify it quite easily, I think."
It was Red Hugh's wish to be buried in the Church of St Francis in Valladolid, and this was done.
Ludhaigh Ó Cléirigh, the 17th century Donegal poet and historian, described his burial: "His body was taken to Valladolid, to the King's Court, in a four-wheeled hearse, with great numbers of State Officers, of the Council and of the Royal Guard all round it, with blazing torches and bright flambeaux of beautiful waxlights blazing all around on each side of it.
"He was buried after that in the chapter of the monastery of St Francis with great honour and respect and in the most solemn manner any Gael ever before had been interred."
He is in good company in the Church of St Francis, with the great explorer Christopher Columbus buried nearby.
The archaeological project also aims to bring to light the remains of Columbus, who died May 20, 1506.
Architect Oscar Buron and the team of archaeologists formed by Jesus Misiego and members of the Simancas Historical Institute, Olatz Villanueva, are leading the excavation project, which began last Monday.
In a statement, they said: "The burial in Valladolid of these two characters of such relevance to the world as is the case of Columbus and to relations between Spain and Ireland against their common enemy, England, demonstrate the importance of Spain and specifically of Valladolid for centuries".
While Red Hugh was successful in many areas of life, his love life was less so.
He married Rose O'Neill, the daughter of his ally Hugh O'Neill, the Earl of Tyrone.
The partnership was an unhappy one that never produced a child.
Red Hugh tried twice to end the marriage before he eventually left for the ill-fated trip to Spain.
While it can be presumed Red Hugh did have red hair, nobody actually knows for sure.
"I have this lovely painting of this fella with red hair, but there is no portrait of O'Donnell in existence," Mr Morgan explained.
"They have put up statues of his at various battles, but nobody actually knows.
"We can presume he did have red hair given his name, unless some other part of him was red."