Thomas Parnell was an Irish poet and clergyman. Samuel Johnson included Dr. Parnell in his famous volume Lives of the Most Eminent English Poets. Parnell's poem "My Days Have Been So Wondrous Free" was set by Francis Hopkinson in 1759 and is considered the first American art song.
Parnell participated in the satirical Scriblerus Club with his friends Alexander Pope and Jonathan Swift. He also contributed to the witty publication The Spectator, and aided Pope in his translation of The Iliad. He was one of the so-called "Graveyard Poets"--his “A Night-Piece on Death,” widely considered the first "Graveyard School" poem, was published posthumously in Poems on Several Occasions, collected and edited by Alexander Pope and published in 1721.
Sources: Wikipedia, PoemHunter.com