Thomas was born in Swansea, in South Wales: his father David, who was a writer and possessed a degree in English, brought his son up to speak English rather than Dylan's mother's native Welsh. Dylan Thomas' middle name, "Marlais", came from the bardic name of his uncle, the Unitarian minister, Gwilym Marles (whose real name was William Thomas).
Thomas' childhood was spent largely in Swansea, with regular summer trips to visit his mother's family on their Carmarthen farm. These rural sojourns, and their contrast with the town life of Swansea, would inform much of his work, notably many short stories and radio essays and the poem "Fern Hill".
Dylan Thomas is widely considered one of the greatest 20th century poets writing in English, frequently mentioned alongside Frost, Yeats, and T S Eliot in lists of the century's most important poets. He remains the leading figure in Anglo-Welsh literature.
His vivid and often fantastic imagery was a rejection of the trends in 20th Century verse: while his contemporaries gradually altered their writing to serious topical verse (political and social concerns were often expressed), Thomas gave himself over to his passionately felt emotions, and his writing is often both intensely personal and fiercely lyrical. Thomas, in many ways, was more in alignment with the Romantics than he was with the poets of his era (Auden and Eliot, to name but two).
He is particularly remembered for the remarkable radio-play Under Milk Wood, for his poem "Do Not Go Gentle Into That Good Night," which is generally interpreted as a plea to his dying father to hold onto life, and for the short story A Child's Christmas in Wales.
He collapsed at the Hotel Chelsea after drinking heavily while in New York City on a promotional tour and later died at St Vincent's hospital. Following his death, his body was brought back to Wales for burial in the village churchyard at Laugharne, Pembrokeshire, where he had enjoyed his happiest days. In 1994, his widow, Caitlin, was buried alongside him. Their former home, the Boat House, Laugharne, is now a memorial to Dylan.
There are many memorials to Dylan Thomas in his home town of Swansea, including a statue in the maritime quarter, the Dylan Thomas Theatre, and the Dylan Thomas Centre. The latter building, formerly the Guildhall, was opened by U.S. President Jimmy Carter, one of Thomas's most famous fans, following its conversion. It is now a literature centre, where exhibitions and lectures are held, and is the setting for the city's annual Dylan Thomas Festival.
Another monument to Thomas stands in Cwmdonkin Park, close to his birthplace; this was one of his favourite childhood haunts. The memorial is inscribed with lines from one of his best-loved poems, "Fern Hill". Several of the pubs in Swansea also have associations with the poet.