Few churchmen have been so maligned as Pelagius in the Christian West. For nearly 1,500 years, all that anyone has known of the British monk’s theology has come from what his opponents said about him — and when one’s opponents are as eminent as Augustine and Jerome, the chance of getting a fair hearing is not great. Consequently, it has been easy to lay all manner of pernicious heresies at Pelagius’s doorstep.