"Do not go gentle into that good night" by Dylan Thomas is the Songs of Eretz Poem of the Day for May 14, 2014. A link to this famous villanelle as well as a nice explanation of the poetic form may be found here: http://www.poets.org/poetsorg/text/poetic-form-villanelle. The poem was first published in Thomas' collection In Country Sleep, And Other Poems in 1952.
Native Welshman Dylan Thomas (1914 - 1953) (pictured) dropped out of high school at the age of sixteen in order to pursue his literary career. He went on to become a famous poet, radio broadcaster, and screenwriter. His notoriously wild lifestyle and alcohol binges would lead him to an early grave and saint-like status among his followers. Reference to this and additional biographical information may be found here: http://www.poets.org/poetsorg/poet/dylan-thomas.
Traditional villanelle's have pastoral themes, but contemporary poets have applied the form to different subjects. In "Do not go gentle," Thomas chose the theme of fighting to stay alive in the face of old age, failure, and looming death.
In the final quatrain, Thomas refers to "my father" with a lower case "f" for "father" but also to "that sad height." "Height" evokes "Father" with a capital "F" as in God the Father. His use of "my" implies that Thomas refers to his own father. Perhaps he refers to all "fathers," which is to say all men who will eventually find themselves facing the end of their lives.