The deep red early-morning sun, rising above the rooftops of Madrid in anticipation of the coming day, reflected my own feelings. I stood watching from my hotel window, full of hope for what lay ahead, confident that by the following evening, 65 years since the start of the Spanish Civil War, the misty details of my father's contribution to the fight against fascism would be clearer.

My dad, Gerry Doran, who grew up in Dublin, headed off in December 1936 with his fellow Irish International Brigaders, or brigadistas. With almost 200 other Irishmen, he had been rallied to the cause by Frank Ryan, his old Fianna ╔ireann compatriot, and responded without a backward glance.

At a time when Ireland was torn apart by hysterical ranting from both the pulpit and the establishment, the men who went to Spain to defend the democratically elected government against Franco were castigated, excommunicated and branded communists.

It has taken more than 50 years for them to be exonerated and for their countrymen formally to recognise the immense sacrifices they made. Sadly, for many of them - including my father - it all came too late.

Although he had been seriously injured during fighting on Christmas Eve 1936, my father did not die on the bloody battlefields of Cordoba, Jarama, Brunete or the Ebro, like so many of his brothers in arms. Yet, because of the general attitude in Ireland when he came back, I have no doubt that part of him died with them.

Growing up in Scotland, we children were too young to understand it all then; but now, some 25 years since his death, we have started to piece together my father's story, and there have been times when the information has fallen into our laps.

In 1981, while flicking through a Sunday newspaper, I was about to pass over some photographs when the shape of a familiar hand caught my eye. Tracing up, I saw my father's face smiling out from the page. He was surrounded by other men, also in khaki fatigues, all smiling for the camera in the Spanish winter sun.

I knew my father had fought at Cordoba on Christmas Eve 1936. Was this photograph taken there, just hours before the battle? Did those other men die there?

I decided to find out more. Through books and the Internet, especially the account of James Prendergast, an Irishman, I began to piece together those few horrific days when, under the command of George Nathan and Kit Conway, the brigade withstood the might of Franco's Army of Africa.

Then there was my father's account. As he moved forward under intense aerial bombardment, a bullet pierced his upper arm. More seriously, a piece of shrapnel became embedded in his helmet, forcing it down into his skull.

Several men had been hit at the same time and, as they lay on the ground, two stretcher-bearers approached. They could take only one. Lying beside my father, John Meehan from Galway told them: "Take Gerry, he's worse hit than me". Through the skills of a French surgeon, my father survived. He was devastated to find out later that Meehan had perished.

How precarious is life, hanging on such a fragile thread. Had a different decision been made that day, the story may well have been told by the son or daughter of John Meehan. Instead, my sister and I found ourselves in Spain recently, representing our father at the 65th Homage celebration organised by the Asociaci≤n de Amigos de las Brigadas Internacionales - or Friends of the International Brigades Association - and attended by brigadistas and their families, who had travelled from more than 50 countries to share once again that unique camaraderie.

Among them were two of only three Irish brigadistas still alive. Like their comrades, Michael O'Riordan and Bob Doyle have been prolific in recording their own stories and those of their fellow brigadistas, so that subsequent generations can learn from the past. Wherever they went, together with O'Riordan's son Manus, they carried the banner of the Connolly Column, a reminder of the courage and commitment of Frank Ryan's men.

Over the four days in Madrid, what we witnessed was nothing short of miraculous. In spite of all the languages and cultures, there was an immense mutual understanding, an overwhelming desire to communicate and genuine respect and love.

Inevitably, there were moments of dissent. When Emmanuel, an old Polish comrade, became distressed at a young guide's refusal to allow him to leave the bus as it perched on a cliff above Jarama, more patient fellow brigadistas were unsympathetic.

The mood changed, however, when he stripped off his shirt to reveal the wounds he had sustained on this same battlefield, and inadvertently uncovered the tattoo imprinted on his arm at Auschwitz, where he was sent after Spain. The effect on all of us, and in particular Lou, a US brigadista and subsequent liberator of Dachau, was humbling.

There were also moments of overwhelming sadness. As we stood on the Arganda Bridge, liberated by AndrΘ MartΘ and the Italian Garibaldi troops, John McGrotty, the brother of Eamon McGrotty, the former Irish Christian Brother who died at Jarama, dropped a wreath over the parapet.

It was a signal for us all to make our own personal prayers and gestures, as we threw 100 red carnations into the water. And, while singing and remembering, the family of a Scottish brigadista quietly sprinkled his ashes into the slow-flowing, flower-filled water below.

Madrid has been a roller coaster of emotions, swinging from sorrow to elation. Spanish hospitality is legendary. After a typical three-hour, 10-course, four-bottle lunch, the group at my table decided we would sing at the concert that evening. The wine-induced bravado faded as we stood in the wings, realising too late that everyone else on the programme was professional and had been practising for months.

But there is something about singing from the heart. As we performed Christie Moore's Viva La Quince Brigada in front of all those people, silently adding our own dead to those listed, it was not about voice but rather about soul - and if the visit to Spain was about anything, it was about that.

In the course of my time with the brigadistas in Spain, I may not have discovered the missing links to my father's story but, in truth, I found my father.

He was there in the memories and in the integrity of all of those old men, in the warmth of their smiles and in their determination to tell their stories to the world, so that such tyranny is never allowed to triumph again.

Geraldine Abrahams, through Reel Scoop Productions, is scripting a feature film on Frank Ryan's involvement in the Spanish Civil War