Trench is educated at Haileybury and Keble College, Oxford, and is elected a fellow of All Souls College, Oxford. In 1891, after some years spent in traveling, he is appointed an examiner in the Board of Education. He gives up this appointment in 1908 in order to devote himself to literary work.
In 1908 a dramatic symphony, Apollo and the Seaman (Op.51), written by Joseph Holbrooke setting Trench’s poem Apollo and the Seaman is performed, under Thomas Beecham. Trench then moves into theatrical work for a few years becoming director of the Theatre Royal Haymarket in London. Here he collaborates with his friend Thomas Evelyn Scott-Ellis, 8th Baron Howard de Walden. They stage The Blue Bird by Maurice Maeterlinck in 1909, and Henrik Ibsen‘s The Pretenders in 1913.
From his school days Trench has been a writer of verse, and his first volume of poems, Deirdre Wed and other Poems, appears in 1901. It is followed by further poems, notably Apollo and the Seaman, included in New Poems (1907), and Lyrics and Narrative Poems (1911). Among his later publications are an Ode from Italy in time of War (1915), Poems with Fables in Prose (1917) and a poetic play Napoleon (1919), which is produced in London by the Stage Society in 1919. Some of his poems are set to music by Arnold Bax.