Sextus Pompeius Magnus Pius, son of Pompey the Great, fits uneasily into narratives of Rome’s civil war of 49-31BC. Ronald Syme, father of international orthodoxy, stated that Sextus was ‘in reality an adventurer’ who was ‘easily represented as a pirate’. He was wrong. Sextus Pompeius plays havoc with orthodox history. His military success punctures the myth of continuous Caesarian victory. His systematic rescuing of the victims of Triumviral violence belies the claim that only the Caesarian side represented clementia and justice. His naval strategy reveals his commitment to the same cause and ethics as his father and his father’s allies. Indeed, Pompey the Great and his Republican allies can only be understood, Welch shows, by a study of his gifted, resilient and ultimately unlucky son. Welch places Sextus Pompeius at the centre of Rome’s transition from Republic to Empire and so reveals an ideological landscape very different from 20th-century representations.