This year has been a good one for Seamus Heaney. In March he received the David Cohen Prize for a lifetime’s achievement in literature, and his 70th birthday in April was the occasion for numerous tributes and celebrations. Heaney has also returned to the public stage after a period of convalescence following the minor stroke he suffered in 2006. A few days after speaking to him, I join the full-house of 600 for the inaugural event of the Newcastle Centre for the Literary Arts to watch him give a poetry reading. His gives a magnetic performance, polished and yet spontaneous, as he produces poem after marvellous poem for a rapt audience.

Heaney was already an exceptionally popular and lauded poet when he won the Nobel Prize in 1995; and yet the almost universal appeal of his work might not have been predicted, for his subject matter is often intensely local: he repeatedly returns to childhood reminiscences, tributes and elegies to friends and loved ones, and explorations of the rural landscapes and traditions of Northern Ireland. Heaney’s greatness lies in his acute awareness of the possibilities of the English language and his ability to unlock its political, historical and acoustic potential. One of the principle ways in which he has renewed his art is by translation.

Translation obliges a writer to re-examine their resources, to check that their linguistic house is in order and to make allowances and accommodations. It invariably proves to be a enriching experience.Heaney’s excavations have yielded translations of Old Irish in Sweeney Astray, Old English in Beowulf, and Scots Gaelic in his versions of Sorley MacLean’s poetry. He has also translated work by Virgil, Horace, Sophocles, Dante and Rilke. How does he decide which poems to translate? His answer suggests that it isn’t always a decision. “Some things swim up like ideas for original poems, unpredictably, but with a flicker of promise, a sense that you’ll come into your own if you proceed with the material.”

Heaney’s latest translation is of Robert Henryson’s medieval masterpiece The Testament of Cresseid. Little is known about Henryson: he was born in the 1420s and died around 1500; he is associated with Dunfermline and Glasgow and he wrote in Lowland Scots. Cresseid is a continuation of Chaucer’s Troilus and Criseyde. With the Trojan War at its height, Cresseid, a Trojan woman, abandons her lover Troilus for the Greek warrior Diomede. Diomede tires of her and moves on, leading Cresseid to inadvertently incur the wrath of the gods by cursing Venus. Cresseid’s punishment is to be made ugly overnight. Forced to live among the lepers, she utters a long lament:

O sop of sorrow, sunk and steeped in care!

O poor Cresseid! Now and for evermore

Delight on earth is gone, and all your joy . . .

Finally, in a cruelly ironic twist, Troilus gives her some gold when she is begging, but fails to recognise her:

And at a glance it came into his thought

That he some time before had seen her face.

But she was in such state he knew her not . . .

It is a bleakly beautiful work — but Heaney’s version of Cresseid also contains seven of Henryson’s adaptations of Aesop’s fables, which feel like a balm after Cresseid’s tale of suffering. The Testament and the fables are written in the same form, the exacting seven-line stanza of the rhyme royal, but the difference in tone meant that the experience of translating them was quite distinct. “Doing a stanza of one of those fables was like the experience I used to love of inflating a leather football. You’d pump it so tight that the thing seemed to get lighter, then you’d lace it and bounce it hard and quick and be delighted by the sheer buoyancy and trimness.” He thinks about this for a moment. “It should be said that the stanzas of The Testament of Cresseid were more burdened than bouncy. The fables — to quote Yeats — trod with a lighter tread.”

Heaney shows why he makes such a good match for Henryson. The combination of the football image and allusion to Yeats is reminiscent of Henryson’s fables, which blend elevated rhetoric with an almost folksy wisdom. Both poets bring the reader into their confidence effortlessly:

In homely language and rough turns of speech

I have to write, for always eloquence

And rhetoric remained beyond my reach.

Therefore I humbly pray your reverence

That if you find here through my negligence

Anything much shortened — or protracted —

By your good will and good grace you’ll correct it.

Henryson is being a little coy in these lines: his poetry displays skill rather than “rough turns of speech”. Heaney shares something of this mischievous spirit, as when he switches from donnish observation (of Beowulf: “Those verses were definitely more calculés than donnés”) to boyish enthusiasm (of Henryson’s fables: “The more I trampolined off the original the more I enjoyed the job”).Translating Beowulf proved to be a painstaking process: commissioned by editors at W. W. Norton in 1984, it appeared in 1999. By contrast, the Henryson translations were labours of love. “I saw a manuscript of a Henryson fable in an exhibition in the British Library and all of sudden I was awake to the voice and wanted, as I’ve said, to hum along with him.”

In both cases, Heaney says that it was essential to feel “some promise, some possibility of imaginative or linguistic purchase” with the original. “With the Beowulf, for example, there was an old familiarity and even a sense of affiliation to the Anglo-Saxon language. When I was a student, the first half of the epic was a set text, but other poems on the course meant more to me at that stage. I loved the emotional weather of The Wanderer and The Seafarer and preferred the swifter, plainer narrative of The Battle of Maldon to Beowulf. But at the same time, I did develop a feel for the ‘blunt-tongued Anglo-Saxons’, as Borges called them.”

A breakthrough moment in his Beowulf translation came when Heaney discovered that some Old English words were already familiar to him as Ulster dialect, such as “thole”, meaning “to suffer”. A similar moment occurred in the Henryson translation when Heaney became aware of the Scottish element in Ulster speech, and “the hidden Scotland” at the back of his ear. I ask him about the importance of these recognition scenes. “ ‘Recognition scene’ is exactly right. Unless there’s some kind of mating call being exchanged between your sounds and the sound of the original, or something cognate in your temperament or knowledge of life, it’s hard to proceed.”

Not everything in Henryson’s work requires updating; it belongs “in the eternal present of the perfectly pitched”, according to Heaney. Some aspects of Henryson’s sensibility seem particularly modern. His portrayal of Cresseid is sympathetic, and her story has a wider resonance: set against the backdrop of the Trojan War, we see a woman aged prematurely, made homeless and reduced to begging — it would be easy to depict her as the precursor of displaced victims of contemporary wars. But Heaney denies seeking out any contemporary parallels, pointing instead to the “temperamental affinity” he feels with Henryson, just as he felt it with the Beowulf poet. “What I love about both of them is a stern quality, tempered in Henryson’s case by humour and tenderness and in the case of the Old English poet by his Christian meditativeness and resignation.”

Is there a limit to the “temperamental affinity” Heaney feels with the poets he translates? Has any poet remained stubbornly unknowable? “The one place where I have a genuine sense of otherness — and the difficulty of apprehending never mind rendering it — is in Virgil. I’ve been having a go at Book VI of The Aeneid, and am conscious of the difference between that world and ours. I believe I’m realising that because I know enough Latin to arrive at the frontier of literal meaning but can only gaze across into the heartland of deeper apprehension.” It is a frontier that Heaney, the most sure-footed of poets, has led us across many times.

Seamus Heaney’s translation of The Testament of Cresseid & Seven Fables by Robert Henryson is published by Faber and Faber at £12.99. To order it for £11.69 and with free p&p call 0845 2712134

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