In his biography, 'The Great O'Neill', Seán Ó Faoláin portrays the exile O'Neill's last days in Rome as a period of despair and disillusionment.
This really was not how it was supposed to end. In 1598, after the Battle of the Yellow Ford, there was little reason to suppose the defeat of the Gaelic world of Ulster was inevitable. A twin policy of sword and scorched earth clinically delivered from the English power base of Dublin had decimated Gaelic society in the southern provinces throughout the 16th Century but the Gaels of Ulster, led by O'Neill and Aodh Ruaidh Uí Dhomhnaill, had every reason to expect their northern lands to remain apart from the 'Pale'.
At the Yellow Ford, O'Neill and O'Donnell had routed an advancing English army of 4,000 men (six regiments of foot with cavalry support).
The English force sustained heavy losses in the battle and its immediate aftermath, with the 2,000 survivors eventually being shipped from Newry to the safety of Dublin after negotiating safe passage.
From that high point, with The Great O'Neill lauded by the enemies of Elizabethan England (ie most of Europe), and with the prospect of Spanish aid, the Gaels of Ulster could reasonably countenance the re-conquest of the rest of Ireland from English rule with some confidence.
The tactical disaster of 1601 in Kinsale, Co Cork, far from their northern stronghold, changed everything, and the Flight of the Earls resulted in O'Neill and his entourage in exile in Rome.
Despite many setbacks and tribulations, O'Neill continued to lobby the Spanish Court for the military assistance to re-enter the field of battle. It wasn't to be, and the Irish nobility steadily succumbed to the fevers and malaria that afflicted them in Rome.
At least seven, but possibly eleven or more, of the O'Neill and O'Donnell party were buried in the Spanish sponsored church of St Pietro in Montorio, high on the Gianicolo hill that overlooks Rome.
At first, the deaths of the party received all the ritual and ceremony of European nobles of the first rank. The ornate marble ingraved grave-slabs inlaid on the floor, above the underground burial vaults, record the homage paid to The Great O'Neill's son, also Hugh, and to the O'Donnells, Hugh and Cathbarr (sons of Aodh Ruaidh).
By the time of Hugh O'Neill's own death, on this day in 1616, only a basic slab was required, as described by a record made in 1664. Indeed, although the ornate grave slabs of his son and the two O'Donnells are still intact, O'Neill's own marble slab has since disappeared - possibly during the upheaval of the 'Risorgimento', when Garibaldi's forces engaged French forces on the Gianicolo hill (with St Pietro suffering structural damage from the ensuing cannon-fire).
Due to the records made in 1664, we do know where the original was placed, and we do know the original Latin inscription that marked the passing of The Great O'Neill: "D.O.M. HUGONIS PRINCIPIS ONELLI OSSA" (To God the Best and the Greatest. The bones of Prince Hugh O’Neill).
Using this record, a replica plaque was laid in place of the original slab by Cardinal Tomás Ó Fiaich in 1989.
The original slab may well have disappeared forever, smashed to pieces by an under pressure builder. However, there is also the tantalising prospect that the Great O'Neill's grave-slab is still there, but moved and placed upside down, waiting to be rediscovered.
O'Neill's exile turned the Gaelic world upside down, and, with hindsight, we might now say that was the beginning of the end for Gaelic Ireland, However, the encouraging thing about the cycle of history is that, if you wait long enough, the great wheel turns.
If the Great O'Neill were to return now, he might retrace his steps along the Callan River, along the Yellow Ford, on to his old stronghold of Dungannon, on to the O'Neill inauguration site at Tullyhoge, across the great plains of Ulster where his vast herds of cattle once roamed, and on to Rathmullan where he sailed to exile through Lough Swilly.
On this fanciful journey, Aodh Mór would surely find some solace in the irrefutable evidence that Gaelic Ireland is not dead and gone, after all.
All languages shift and modulate over a space of 400 years, but The O'Neill would recognise the Gaelic voices to be heard today all along that route, ever clearer, ever louder.
Maybe, if his marble slab is ever found and turned the right way up, we may take it as an omen that his Gaelic Ulster was never really lost, it was just waiting to be found again, when the time is right.
For an indepth study of the Irish burials at St Pietro, see the NUI Galway Project Description: "San Pietro in Montorio -Burial Place of the Exiled Irish in Rome 16...."
For an insight to Hugh O'Neill: "The Great O'Neill: A Biography of Hugh O'Neill, Earl of Tyrone, 1550 -1616. Seán Ó Faoláin, Dufour Edition, 1997.