Shapur I, king of Persia, mounts his horse by treading on the back of the Roman emperor Valerian. After a series of wars against the Romans, Shapur defeated Valerian at Edessa in A.D. 260 and kept him captive for the rest of his life. Boccaccio speaks directly to Valerian in the text, telling him that he dishonored the people of Rome and should have killed himself to avoid such humiliation. He says that Valerian deserved his fate because he had oppressed Christians, cursed the name of God, and persecuted the Church, while allowing pagans to worship false gods. The word Ancram, which appears below the miniature, can be found on a number of folios in this manuscript. It is the signature of the Earl of Ancram, who owned the manuscript in the 1700s.