Remembrance Sunday commemorates the dead of the Great War: but it also remembers the dead of the Second World War, which began 70 years ago next August.

Most of what follows has never been published before. Why? Because I found it.

On September 4, 1939, the day after Britain declared war, five RAF bombers attacked the German naval base at Wilhelmshaven. Four were shot down, the first flown by Pilot Officer William Murphy (23), the son of William and Katherine Murphy, of Mitchelstown, Co Cork. The sole survivor from the four doomed aircraft was, rather strangely, Laurence Slattery of Thurles, Co Tipperary. Billie Murphy was thus both the first Irish and British victim of the Second World War.

We can, if only arbitrarily, identify the last Irish death of the war: Aircraftman 2nd class Timothy O'Sullivan, aged 20, at home in Limerick in September 1945. But uncountable others later perished of their injuries, or the madness of war. Poor Slattery, for example, spent six, bitter years in a POW camp, before returning to Ireland. A broken man, he lived alone in a room above a shop in Thurles, until his death in the 1960s.

About 5,000 Irishmen died serving with the British Army in the Second World War — rather more from the South than from the North. This means that roughly 53,000 volunteers served from southern Ireland, and 52,000 from the North. With air-force, merchant marine and naval losses, independent Ireland's wartime death-toll alone might be four thousand. For those who so keenly trumpet northern unionist devotion to the allied cause, the figures are sobering. Of the 478 Irish-born British army officers killed, 345 (72%) came from the South. Four Irish brigadiers were killed: all southerners. Thirty-three Irish lieutenant-colonels were killed: only three from the North. Eight southern Irish chaplains were killed, two northern. Fifty southerners (including my uncle, after whom I was later named) died in the Royal Army Medical Corps, and 28 from the North. In the Intelligence Corps, one northern death, seven southern. Thirty-eight female southern volunteers died, 15 from the North. One northerner — a Catholic — won the Victoria Cross: as did five, southern, Irish-born Catholics.

A Dubliner, Private James Scully, won the Pioneer Corps' only George Cross, for gallantry during the Liverpool Blitz in the winter of 1941. Another Irish Catholic won the GC that evil season, though posthumously: Captain Michael Blaney from Newry, an NUI engineering graduate, whose award reflected his extraordinary courage in defusing a series of unexploded bombs in London when his death — as he knew it would be — was inevitable. And as for the mystery of motivation, why, I merely draw your attention to a 19-year-old Cork-born sailor who died on HMS Glorious in 1940; Patrick Pearse Murphy. Tragedy came not often singly. In May 1940, the war's first RAF VC went posthumously to Flight Lieutenant Donald Garland, a Dun Laoghaire Catholic. By war's end, his three brothers — Patrick, John and Desmond — had also perished in RAF service. John McFall, from Monaghan, was killed with the Ulster Rifles in April 1941.

A year later, his parents' one surviving child, Sergeant Pilot Joseph McFall, was fatally injured in action. Dying a year apart, in different services, by extraordinary coincidence, these two boys are buried in the same cemetery in Hereford.

Flying Officer Charles Bomford of Ballycommon, Tipperary, was killed during the fall of France in 1940. Four years later, his only brother Richard, was killed in action in Italy.

On April 11, 1943, Bartholomew McKeon, from a southern Catholic family, was shot down and killed in North Africa. Just a week later, his only surviving brother, William, suffered a similar fate in the North Atlantic.

Not long afterwards, Flight Lieutenant Arthur Patrick Dowse, from Ard Brugha Villas, Dalkey, stayed at the controls of his doomed Lancaster to enable his crew to bail out over France. All six survived. He did not. Eighteen months later, his only surviving brother, Dick, was shot down and killed, aged 21.

From D-Day to VE Day, eight hundred and fifty Irishmen serving in the British Army were killed in the liberation of North Western Europe. Almost half of them — 421 — were from the South. Six hundred and forty four Irishmen died in the land-battles to free Italy, slightly over half — 326 — from the 26-counties. Nearly 300 southerners died fighting in Malaya and Burma.

As yet uncounted others died with the Indian army: 60% of the officers of one Gurkha battalion — in which my neighbour (and true gentleman) Patrick Foley, had the honour to serve — were Irish.

From May 1945, newspapers in the Republic began to carry a roll of honour of Irish military personnel whose deaths had been concealed by the censors. One death notice from ‘E.G.S, a friend’, for a Royal Artillery subaltern killed in 1944, stands out.

It read: ‘Williams, in memory of a dear friend, a noble character, a loyal companion, and former student. Lieutenant Sean Williams RA (TCD) who gave his life so that I and others might live to pursue our ideals in freedom.’

Quite.