I was reading a memoir of Nevill Coghill (Inkling and Oxford Professor of English - a scholar and translator of Chaucer and Langland) - and I was struck by the remarkable, indeed truly amazing, concentration of literary genius among the Protestant Irish gentry (the Anglo Irish) in the days when Ireland was ruled by Britain.
With no effort, I came up with Jonathan Swift, Richard Brinsley Sheridan, Oliver Goldsmith, Richard Steele, Oscar Wilde, George Bernard Shaw, WB Yeats, J.M Synge, Samuel Beckett, CS Lewis - all of whom are of the first rank in their genres within English Literature - plus a similar sized group of minor or lesser-known figures.
Indeed, considering that there are only few canonical playwrights, this is an extraordinarily high proportion (the only ones missing before the 20th century are ?Marlowe, Wm. Shakespeare (of course), ?Ben Jonson, ?Congreve...
...but really I am scratching around for anyone other than The Bard who is performed as often and provide such enjoyment as Sheridan (The Rivals, and School for Scandal), Goldsmith (She Stoops to Conquer), Wilde (mostly The Importance of Being Earnest) and (of course) Shaw (with a couple of dozen plays done frequently - perhaps even more than Shakespeare himself?).
Among the indigenous Irish I would only put James Joyce and Flann O'Brien into the same quality bracket.
At any rate, the number of Anglo Irish/ Protestant Ascendancy writers of the first or second rank in English Literature is grossly disproportionate to the small absolute size and minority status of their population.
And gives rise to the interesting question of the nature of the (much vaunted) Irish literary genius: it was certainly real, but actually mostly consisted of the English-living-in-Ireland (since expelled).
Note: Another first-ranker (among English poets) is Edmund Spenser, who was among the first of the English upper class to settle in Ireland as recent conquerers: the first of the great Anglo-Irish literary figures.