The Greatest Poet...
For me the answer is easy - W.B. Yeats.
In December 1923, nearly 86 years ago, Yeats won the Nobel Prize for literature and made much of the fact that the recognition came shortly after Ireland had gained independence. His recognition, Yeats contended, was an acknowledgement of the quality of Irish literature. Perhaps, but Yeats was an immense talent. In fact, his greatest work - lyrical, beautiful poetry - came after he received the big prize that had been awarded largely for his work as a playwright.
One of my favorites poems is called The Choice:
The intellect of man is forced to choose Perfection of the life, or of the work,
And if it take the second must refuse A heavenly mansion, raging in the dark.
When all that story's finished, what's the news?
In luck or out the toil has left its mark:
That old perplexity an empty purse,
Or the day's vanity, the night's remorse.
I also like Yeats because he was a man of the world, indeed he served in the Irish Senate where he became a major voice celebrating Irish culture.
Pour a little Irish whiskey on a cold November night and open Yeats' collected works. You'll find some magic.