High Quality Content by WIKIPEDIA articles! Sir Isumbras is a medieval metrical romance written in Middle English and found in no fewer than nine manuscripts dating to the fifteenth century. This popular romance must have been circulating in England before 1320, because William of Nassington, in his work Speculum Vitae, which dates from this time, mentions feats of arms and other `vanities`, such as those found in stories of Sir Guy of Warwick, Bevis of Hampton, Octavian and Sir Isumbras. Unlike the other three stories, the Middle English Sir Isumbras is not a translation of an Old French original.