One of the first retrospective accounts of Oliver Cromwell’s early career, Andrew Marvell’s ‘An Horatian Ode upon Cromwell’s Return from Ireland’ (1650), maintained that its subject was difficult to capture. Perhaps the finest political poem in the English language, it was written shortly after Cromwell’s return from a brutally successful military campaign overseas, which witnessed infamous atrocities at Drogheda and Wexford.