Poetry was a part of Dylan Thomas' life from a very young age. Perhaps Dylan's most critically acclaimed of his poems is "Do not go gentle into that good night." Francis Scarfe in his book, Dylan Thomas: A Pioneer, states that "...At his best, Thomas reminds us of the Old Testament, James Joyce and Hopkins all at once." The Welsh language appears in some of his poems but the influence of his Welsh childhood filled only the mood of his verse. Thomas did not speak Welsh.

Thomas had three themes in his poems: love, birth and death. Eighteen Poems, published in 1934 when Dylan Thomas was nineteen, became his first critically acclaimed collection of poems. Poems from this collection show his style at his young age. Examples include the seasonal celebration "I see the boys of summer" and, poem about life before birth, "Before I knocked".

When a close relative died Dylan composed a poem to mourn her death. He made poems that focused on the sanctity of death and birth and collected them for his book, Deaths and Entrances, published in 1945 and included such famous works as "Fern Hill" and "A Refusal to Mourn the Death, by Fire, of a Child in London." Thomas truly brings out the feeling of mourning in these poems.