Vicarious liability was, and it remains, curiously unsatisfactory. After a period of stability from the Middle Ages into the early modern period in the late seventeenth into the early eighteenth century, the existing law of vicarious liability began to be challenged. The mid-nineteenth century saw another reappraisal coinciding with the rise of notions of fault. The period that follows, from the late nineteenth century until after the Second World War period has not attracted much comment. One key debate in this period and earlier which provides a useful lens to examine the doctrine was whether vicarious liability should be properly characterised as a master's or servant's tort theory. The history of the doctrine during this period goes some way to explaining why the modern law remains incoherent.