Just outside the city of Galway on Ireland's west coast is the tiny town of Gort. And a few miles from Gort stands a 15th century Norman tower called Thoor Ballylee. It's a square, four-story castle with one room per floor and, famously, a winding stair for a spine. There the poet William Yeats and his family lived from 1921 to 1929, a span which contained both the Irish Civil War and the poet's time as a senator in the newly created Irish Free State.

As it had for its first occupants, Thoor Ballylee served Yeats as a stronghold, a literal and powerfully symbolic retreat from the chaotic rigors of public life. It rises amid Galway's green vistas on the opposite coast of Ireland's sooty, bustling capital, Dublin. What could be more poetic than imagining Ireland's greatest bard atop his ancient tower looking out over the land while his country, so recently granted independence, tears itself apart? No surprise, then, that this deeply poetic structure would affix its name to two of Yeats's finest books, The Tower and The Winding Stair and Other Poems.

In many ways, the tower is the symbol of a lifelong tension in Yeats between a private, contemplative vocation and his public persona in which politics played such a large part. It's a major theme in his work, too, addressed directly in poems such as "A Dialogue of Self and Soul" and "The Choice" (both from The Winding Stair), the latter of which begins: "The intellect of man is forced to choose//Perfection of the life, or of the work". In this respect, Yeats parallels his fellow countryman Oscar Wilde, who debated whether to pour his genius into his art or his life (Wilde, of course, couldn't really decide, so he generously poured it into both.)

For all the tranquility of his tower, William Butler Yeats was a man who spent most of his long life at the crossroads of art and politics. Really, given his ancestry and his calling, he was a walking crossroads. Even before his birth, a world of art and politics awaited him. His father was John Butler Yeats, one of Ireland's best known painters. William was born in Dublin in 1865. That takes care of the politics.

Of course, it's far more complex. Yes, to be an Irish artist of any stripe implies a tangled relationship with political concerns. But Yeats, by dint of when he lived and his social stratum, was thrown–to use a term he favored–into the gyre. Yeats was born into the Ascendancy, Ireland's Protestant, Anglo-Irish ruling class. It may seem paradoxical to the outsider, but that meant that he was given a huge head start on becoming a fervent nationalist.

From Jonathan Swift to Wolfe Tone, Lord Edward FitzGerald, and Robert Emmet through Charles Stewart Parnell, the Protestant Ascendancy continuously furnished leaders in the causes of Irish equality with England, home rule, or independence outright.

Initially, Yeats threw his weight behind the artistic calling. His early collections, especially The Rose (1893) and The Wind Among the Reeds (1899), reflect his allegiance to Romantic and pre-Raphaelite aesthetics, as well as his immersion in Irish folklore and mythology. He uses inverted syntax and anachronistic, often precious diction, his poems full of "pearl-pale hand(s)," "cloud-pale eyelids" and "dream-dimmed eyes".

The pale poet and his wan words needed to get out in the sun! And Yeats begins to toughen up his language and his attitude as early as "The Lake Isle of Innisfree" from The Rose. In what became his most well-known poem, Yeats pines for the romanticized seclusion of this pastoral setting. Some syntactical inversions are still there–his cabin is "of clay and wattles made" and he stands on "pavements grey"–but the poem is narrated from a modern, urban, and most unromantic setting.

With a shift in Yeats's poetic diction towards the hard, sometimes ugly facts of the modern world comes a willingness to roll up his sleeves and get involved in the dirty work of socio-political struggles. Writing soon after Yeats's death in 1939, the American poet Archibald MacLeish put it this way: "Between the faint, vague, lovely wanderings of his first Romantic poems and the strong presentness, the urgent voice, of such a poem as 'Byzantium' is not only the distance between mediocrity and greatness but the distance also between a poet of private speech and the satin salons and a poet of public speech and the world."

Yeats was a member of several organizations dedicated to Irish independence, including the Irish National Alliance (also known as the Irish National Brotherhood) and the Irish Republican Brotherhood (IRB), a precursor to the Irish Republican Army. While it's not known exactly when he joined the revolutionary IRB, scholarship points to 1886, when Yeats was 21. Yeats was also close friends with John O'Leary, the 19th century Irish separatist, and Arthur Griffith, editor of the United Irishman newspaper and founder of Sinn Féin, the Irish nationalist political movement whose name means "ourselves alone."

And still the allure of artistic solitude, as well as a lifelong devotion to mysticism and the occult, tempered the energies of Yeats as would-be revolutionary. More pragmatically, Yeats also had second thoughts about the people, worrying that sectarian violence, especially pent-up reprisals by Ireland's Catholic majority, would rage uncontrolled in an autonomous Ireland. As his biographer, Roy Foster, points out, Yeats had modified his political stance so that by 1912 he advocated home rule, no longer espousing independence. No better summary of Yeats's change of heart can be found than his poem "September 1913" (published most publicly in the Irish Times) and its repeated lines: "Romantic Ireland's dead and gone,//It's with O'Leary in the grave."

As it did to so many Irish, the Easter Rising of 1916 (organized by the IRB's Military Council) astonished Yeats. Soon after, he memorialized it in one of his greatest poems, "Easter, 1916," even conceding that he had underestimated his former revolutionary comrades, but he would not have the poem published until 1920.

Then, as Yeats himself wrote in "Easter 1916," all changed utterly. The draconian British reaction to the Easter Rising, especially the firing squad executions conducted behind closed doors at Kilmainham Gaol of fourteen of the rebellion's leaders, turned an ambivalent public towards the rebels and their cause. Out of the ashes of failed insurrection, a successful revolution would arise.

Now Yeats, who had remained tellingly silent throughout the revolution, recast himself as one of the senior figures in a long struggle for nationhood, the vocal but even-tempered advocate of a new, essentially independent Ireland. Exactly how independent Ireland was, however, would spark a civil war. Yeats, nearing 60, remained dedicated to the newly created government. His stature would be further enhanced in 1923 with the award of the Nobel Prize for Literature, the first Irishman to be so honored.

The world-renowned poet and playwright served as a senator in the Irish Free State from 1922 until 1928. Imagine if Walt Whitman had served as a U.S. senator or Robert Frost had been a three-term Congressman.

Few poets get better with age; Yeats was a rare exception. He died in 1939. For the last ten years of his life, he returned to his art, writing what are arguably his best poems (contained in the collections New Poems and Last Poems), along with dramas and essay collections. His work in those ten years alone has generated reams of scholarly commentary. And it's not only the quality of his poetry but the sheer range of his material—bawdy ballads, profound meditations, barbed social commentary, aesthetics, politics, and always a dose of the esoteric.

In reading his last collections you get the sense that the poet is assembling a massive catalog of the people, places, and ideas he cherished, a marshalling of memories, a final roll-call Yeats wants to render lapidary: Eva Gore-Booth and Con Markiewicz, Shelley, Oliver Goldsmith, Jonathan Swift, Bishop Berkeley, Edmund Burke, Grattan, Coole Park, Phidias, John Synge, Hugh Lane, Mohini Chatterjee, Byzantium, Parnell, Emmet, FitzGerald, Tone, Hamlet, Standish O'Grady, Augusta Gregory, Maud Gonne, Roger Casement, Michael Angelo [sic], Quattrocento, Blake, Ben Bulben in County Sligo, Connolly, Patrick Pearse, Cuchulain, Pythagoras, Buddha.

His last poem is called, appropriately enough, "Politics," which Yeats wittily prefaces with a ponderous epigraph from Thomas Mann: "In our time the destiny of man presents its meanings in political terms." (It's very similar to what Strelnikov tells Zhivago in Doctor Zhivago.) Clearly, Yeats isn't buying it. Even as "war and war's alarms" threaten and will soon come crashing down on Europe and a good part of the rest of the world, Yeats seems to say that love and what is personal and intimate will triumph over hatred and its many sinister but ultimately ephemeral manifestations, i.e. nations, states, armies, and dictators. Ever the Romantic, Yeats even opens the poem with inverted syntax.

Yeats spent his life at the crossroads of art and politics; you decide which road he took in the end:

How can I, that girl standing there,
My attention fix
On Roman or on Russian
Or on Spanish politics?
Yet here's a travelled man that knows
What he talks about,
And there's a politician
That has read and thought,
And maybe what they say is true
Of war and war's alarms
But O that I were young again
And held her in my arms!