English poet and martyr remembered for his saintly life as a Jesuit priest and missionary during a time of Protestant persecution and for his religious poetry.

Southwell was educated at Jesuit colleges in France and in Rome. In 1585 he was ordained priest and made prefect of studies at the English College at Rome. He returned to England as a missionary in 1586, when he became chaplain to Anne Howard and spiritual adviser to her husband, the 1st Earl of Arundel (Arundel, Philip Howard, 1st (or 13th) earl of), a recusant imprisoned in the Tower of London. Southwell lived in concealment at Arundel House, writing letters of consolation to persecuted Roman Catholics and making pastoral journeys. His An Epistle of Comfort was printed secretly in 1587; other letters circulated in manuscript.

Southwell was arrested in 1592 while celebrating mass. He was tortured in an attempt to make him reveal the whereabouts of his fellow priests and imprisoned in the Tower of London in solitary confinement. In 1595 he was tried for treason under the anti-Catholic Penal Laws of 1585 and executed. Southwell's devotional lyrics and prose treatises and epistles reflect the ardent piety of his life. His best works achieve an unusual directness and simplicity, and his use of paradox and striking imagery is akin to that of the later Metaphysical poets. He is the foremost representative of Roman Catholic letters in Elizabethan England.