English essayist and poet who died before his considerable talent developed; he is remembered principally as the friend of Alfred Tennyson commemorated in Tennyson's elegy In Memoriam.

Hallam was the son of the English historian Henry Hallam. He met Tennyson at Trinity College, Cambridge (1828), where they joined other artistically and politically progressive students in the club called The Apostles. Hallam defended Tennyson's early work, Poems, Chiefly Lyrical (1830), in a review for the Englishman's Magazine and was engaged to Tennyson's sister Emily (1832). Hallam's prizewinning essays and critically acclaimed poems were collected and printed posthumously by his father, the historian Henry Hallam, in Remains, in Verse and Prose, of Arthur Henry Hallam (1834).