Mr. Heaney was born on a family farm in Londonderry in Northern Ireland but, as a Catholic and a nationalist, chose to live in Dublin. His poems often mined the images of his childhood — the peat bogs, small towns and potato farms — and, in collections like 1975's "North," delved into the sectarian violence that was ripping the North apart, exploring its sorrows and causes, though he avoided becoming a spokesman for the Republican cause.

As his reputation grew in the 1980s and 1990s, he remained an accessible and public writer, a respected translator, broadcaster and, most importantly, a prolific poet with a gifted eye. Publishing more than a dozen major collections of poems between 1966 and 2010, he rose to become one of the most distinctive literary voices of the 20th century. Robert Lowell described him as the "most important Irish poet since Yeats."

"Digging," the first poem in his first collection, "The Death of a Naturalist," described his father digging potatoes and his grandfather digging turf. The last lines seemed to set down his personal manifesto:

The cold smell of potato mould, the squelch and slap

Of soggy peat, the curt cuts of an edge

Through living roots awaken in my head.

But I've no spade to follow men like them.

Between my finger and my thumb

The squat pen rests.

I'll dig with it.

And dig he did, producing a remarkable range of work: love poems, epic poems, poems about conflict and strife, odes to nature, poems addressed to friends, poems for the dead, poems that simply reveled in the sound of the English language. After he gained fame with "Death of Naturalist," Mr. Heaney never eased his pace. His later volumes of poetry include "The Spirit Level," "District and Circle" and "Bog Poems."

Seamus Justin Heaney was born, the eldest of nine children, on April 13, 1939, on a farm called Mossbawn, in County Londonderry, in the western part of the British province of Northern Ireland.

His father, Patrick, a cattle-dealer and farmer, was a dour, unliterary man, suspicious of verbiage. His mother was not literary, but, Mr. Heaney recalled, she used to "recite lists of affixes and suffixes, and Latin roots, with their English meanings, rhymes that formed part of her early schooling in the early part of the century."

All around him, he watched police and public officials of the predominantly Protestant province treat Catholics with disdain, sometimes with cruelty. One of his biographers, Michael Parker, wrote that "It could be argued that while Heaney's exposure to what he now regards as 'cultural colonialism' may have bred feelings of inferiority and insecurity in the short term, in the long term it also honed his sense of identity and provided him with sustenance from two rich traditions."

He proved to be a bright boy and he was sent on a scholarship to St. Columb's College in Derry at the age of 12.

Later he studied for a degree in English at Queen's University in Belfast. He went to work as a schoolteacher, then a lecturer in English at Queen's College and later at Carysfort College, a teacher training college near Dublin. Then in 1972, he gave up full-time academic work to be a freelance writer.

For much of his career, he was under constant pressure to write favorably about the goals of his fellow Catholics, many of whom wanted a Northern Ireland free of British control, and though his work often concerned the violence in Ulster, he saw both sides of the conflict and avoided polemics in support of the Irish Republican Army. He said he was suspicious of extreme positions.

He resented British oppression in Northern Ireland, but admired much in British culture and English literature. He was rare among modern poets in that not only the vast majority of critics and academics praised him, but millions of readers also bought him. By some estimates he was the best-read living poet in the world in recent decades.

The accessibility of his work helped. It had references to Greek and Celtic legend, but was usually clear, often dazzling with images of nature, epiphanies of the soul. He wrote about bogs and rocks and streams and transformed them into the settings for the moral problems in a way that seemed to reach not only agnostic intellectuals, but also believing Catholics.

The Irish Times said in an editorial after he won the Nobel Prize: "Book sales may not mean much in the areas of fiction or biography, but for a poet to sell in the thousands is remarkable proof to his ability to speak in his poems to what are inadequately called 'ordinary people.' Yet the popularity of his work should not be allowed to obscure the fact that this deep, at times profound poetry, forged through hard thinking and an attentive, always tender openness to the world, especially the natural world."

Writing in a collection of his lectures in 1995, "The Redress of Poetry, Mr. Heaney said: "It is in the space between the farmhouse and the playhouse that one discovers what I've called 'the frontier of writing,' the line that divides the actual conditions of our daily lives from the imaginative representations of those conditions in literature."

In the 1984 collection, "Station Island," he wrote: "The main thing is to write for the joy of it. Cultivate a work-lust that imagines its haven like your hands at night, dreaming the sun in the sunspot of a breast. You are fasted now, light-headed, dangerous. Take off from here. And don't be so earnest."

He is survived by his wife, Marie, and his children, Christopher, Michael and Catherine Ann.