Fisherman, philosopher, and polyglot; broadcaster, composer and arranger: Seán Ó Riada occupies a place somewhere between that of a tortured genius and what you could term an iconoclassicist. This year, the 40th anniversary of his death and the 80th anniversary of his birth, offers a timely opportunity to delve beneath the surface of this maestro whose legacy is still debated in both traditional and classical music circles.

Those who have made Ó Riada’s acquaintance second-hand through his music might struggle to understand what all the fuss was about. Who was this man who cut a swathe through our characterisation of Irish cultural identity from the early 1950s to the late 1960s? Was he truly the white knight who rescued traditional music from the lower caste to which it had been consigned? Did Ó Riada’s film scores (in particular, that for Mise Éire ) act as a lightning rod, connecting us emotionally with the story of our own genesis as a nation, or did they exploit a weakness for sentimentality at play beneath the hard-worn veneer of Irish life?

And what of his liturgical works? Hell-bent on writing music for 40 Masses, Ó Riada died after composing the music for two, with his setting for Ag Chríost An Síol embedding itself deep within the psyche of almost anyone who set foot inside a Catholic church over the past five decades.

Ó Riada died at the age of 40, having shaken the foundations of traditional music. In his film scores he unearthed a stateliness in Irish music that had hitherto been untapped. In his use of the harpsichord, he doffed a cap to the musical inheritance bequeathed by Turlough O’Carolan, among others. With Seán Ó Sé and Ceoltóirí Chualann, he gave traditional music its first “pop” hit with their muscular rendition of An Puc Ar Buile . Without Ó Riada’s influence, it’s worth asking, would we be experiencing today the bold inventiveness of The Gloaming, the ambitious compositions of Dave Flynn or the inquisitiveness of the sean-nós singer Iarla Ó Lionáird? One of his students, the pianist and composer Mícheál Ó Súilleabháin, recalls Ó Riada’s charisma, a “numinousity or psychic presence” that filled a room.

“I came to traditional music through him,” Ó Súilleabháin says, “and, in so doing, found it already residing inside myself, tucked away securely in some postcolonial cultural mess that so many of us inherited. He was the first public figure with the necessary panache and courage to break through old modes of cultural thought in the Irish situation. He brought both clarity and vision into play.”

Seán’s son, Peadar Ó Riada, remembers his father as a man with a hunger, an inquisitiveness about the world, which extended to his attempts to teach Peadar, at various intervals, Arabic, Urdu and Mandarin. “It was his love of a nation, that emotion, that’s what meant most to him,” Peadar says. “There’s a word in Irish, ‘tír grá’, which is a translation of patriotism, but it’s different in Irish, because we’re of the land. In our culture, we didn’t own the land. It owned you. That was Seán’s guiding force, and the language that he used to express it was music, because it had no borders and no limits. What he wanted was for us to get our independence culturally. He saw that our culture was as good as anyone else’s.” Ó Riada’s real genius, according to Peadar, was that he didn’t get bogged down in the intellectualisation of music.

“Seán was fearless,” Peadar says. “He didn’t care what others thought about what he did, because you don’t when you’re riding that horse. You don’t worry about falling off. The exhilaration and emotion of the act demand all your attention.”

Garech a Brún, founder of Claddagh Records, was a close friend of Ó Riada’s, and it was in Luggala, a Brún’s Wicklow estate, that his final recording, Ó Riada’s Farewell, was made. “Seán was the most delightful, charming, knowledgeable man that I’ve ever met,” says a Brún. “He had a huge interest in what is now called world music, and he wanted to see a fusion of the arts and, in particular, of music and poetry.” Ó Riada’s film score for George Morrison’s Mise Éire, a film about the 1916 Rising and the War of Independence, had a formative influence on a generation, a Brún suggests. “At that time, Seán was breaking new ground. Everyone in Ireland was ashamed of traditional music, yet everyone reacted positively to his score. At that time it was so ingrained in Irish people that fiddle players, for example, were old-fashioned people with string tying up their trousers. They couldn’t see it as part of a modern Ireland. “Back then, there was one pipemaker, Leo Rowsome, and four pipers. How many are there now? Really, his influence was enormous.”

At the time, there were musicians who declared that Seán Ó Riada did composing in Ireland a great disservice, because he chose to bring classical forms to bear on traditional music. Yet was this not what Grieg had done a century before with Norwegian music and Dvorak with the music of Moravia?

Ó Riada suffered from what his friend the poet John Montague calls a double muse. Montague has written extensively of the composer in his memoir The Pear Is Ripe, and in the poem The Lure . “With Mise Éire,” says Montague, “Seán transformed the whole Irish music scene. But I think the impossibility of reconciling his two gifts, as a composer in a classical vein and as an arranger of traditional music, was an enormous challenge, much as [the poet] Michael Hartnett struggled between writing in English and in Irish.”

Paddy Moloney of The Chieftains was a member of Ceoltóirí Chualann, the group formed by Ó Riada in 1960 that dramatically reinterpreted Irish music, with its orchestrated arrangements and its insistence on affording each player space within the arrangements. This was in stark contrast to the céilí bands of the day, where musicians were in competition with each other.

‘He was a genius, a fantastic brain and a bit of a show-off,” Moloney says with a laugh. “He was so colourful and charismatic. What turned me on to him was Mise Éire and his brilliant arrangement of tunes such as Róisín Dubh . I just loved the way he treated them. I wasn’t satisfied with the céilí band thing either, but maybe he was a little too hard on them. I did disagree with the use of accordions, though. I thought they were too brash, and always out of tune with themselves. Seán was a true traditionalist at heart, and he made a great contribution to the revival of traditional music. He’s been criticised for paying such attention to arranging tunes and putting them into harmonies, but I never disagreed with what he was at.”

For Ó Súilleabháin, the Ó Riada legacy is tangible throughout traditional music today. “In his work with traditional musicians - the actual embodied tradition where the musician came with the music - he was, in my opinion, post-modern in his approach and thinking,” Ó Súilleabháin says. “He was part of a rebalancing of the creative process which had increasingly viewed the performer - musician, actor, dancer, builder, &c. - as a craftsperson, as against the creative high ground of the literate artist: composer, playwright, choreographer, architect. The subversive impact of this turn-about is still working itself through the system on all sorts of levels, largely with a refreshing impact. His legacy, to my mind, is one of a wind of inspiration rather than any one identifiable rock of achievement.

“This is why it is so difficult for people who existed or exist outside his psychic domain to understand what all the fuss was about. The best way into Ó Riada remains the poems written about him: Heaney’s In Memoriam Seán Ó Riada, Kinsella’s A Selected Life and Vertical Man, Montague’s Ó Riada’s Farewell, among others.”

Antoine Ó Coileáin of Gael Linn, on whose label most of Ó Riada’s traditional-music recordings were released, is unequivocal in his belief that his legacy is secure. “I really think he saw into the soul of what the Irish psyche is,” says Ó Coileáin. “His concept of the Irish nation is one that I can relate to, very much. In particular, the historical film scores, Mise Éire and Saoirse, are deeply moving, and capture the quintessential spirit of Ireland.

“And I think that’s why he left an enduring legacy. He also had a kinetic energy that set something in motion that has rolled on through the generations. We can follow the thread through so many groups from the 1970s onwards: from The Bothy Band and Horslips to Relativity. I believe that he was the guiding force, the unseen hand on the shoulder for a lot of those people, so that in a way what we witness today as the thriving state of Irish music is due in very large part to the influence of Ó Riada. He dug deep into the roots of what makes us Irish and inspired tremendous confidence in ourselves. He achieved so much in his short life. He was very much ahead of his time.”