Percy MacKaye (1875–1956) was an American dramatist and poet.
He was born in New York City, New York. He studied at Harvard (1897), before returning to New York City (1900-4) to teach. He subsequently settled in Cornish, New Hampshire.
He wrote the plays The Canterbury Pilgrims in 1903, Sappho and Phaon in 1907, Jeanne D'Arc in 1907, The Scarecrow in 1908, Anti-Matrimony in 1910, and the poetry collection The Far Familiar in 1937. In 1950, MacKaye published The Mystery of Hamlet King of Denmark, or What We Will, a series of four plays written as prequels to William Shakespeare's Hamlet.
In the 1920s, MacKaye was poet in residence at Miami University in Oxford, Ohio. He was the son of actor Steele MacKaye and brother of philosopher James MacKaye and of conservationist Benton MacKaye.
Percy MacKaye is considered to be the first poet of the Atomic Era because of his sonnet "The Atomic Law," which was published in the Christmas 1945 issue of The Churchman.
Fluid the world flowed under us: the hills
Billow on billow of umbrageous green
Heaved us, aghast, to fresh horizons, seen
One rapturous instant, blind with flash of rills
A bomb has fallen over Notre Dame:
Germans have burned another Belgian town:
Russians quelled in the east: England in qualm:
A star a star in the west!
Out of the wave it rose:
And it led us forth on a world-far quest;
Where the mesas scorched and the moorlands froze.
URIEL, you that in the ageless sun
Sit in the awful silences of light,
Singing of vision hid from human sight,—