Cartimandua (flourished mid-1st century ad) was the queen of the Brigantes, a large tribe in northern Britain, whose rule depended upon support from the invading Roman armies.

After concluding a treaty with the emperor Claudius early in his conquest of Britain, which began in ad 43, Cartimandua was faced with a series of revolts by anti-Roman elements among her subjects. In 48, Roman forces intervened for the first time to help her quell these disturbances. Three years later the queen’s forces arrested the leader of the British resistance, Caratacus, who had fled to Brigantium to rally support for his cause, and turned him over to the Romans. In so doing she assured continuation of Roman support. From 52 to 57, when her husband and coruler, Venutius, twice attempted to overthrow her by stirring up anti-Roman sentiment, the Roman legions put down the uprisings. Venutius and Cartimandua were reconciled and reigned together until 69, when she divorced him for his armour bearer, Vellocatus. For the third time Venutius rebelled and this time drove her from the throne. The Romans, preoccupied by the chaotic year of the four emperors, could do nothing until 71, when the new emperor Vespasian defeated the Brigantes under Venutius and annexed their territory. Silver coins minted during the reign of Cartimandua have survived.