The work in its fullest form is divided into nine books, but Gilo's original work apparently only contained five, one each on the siege of Nicaea; the first siege of Antioch; the second siege of Antioch; the capture of Bara, Maʿarrat an-Nuʿman and Tartus; and the fall of Jerusalem. With the Charleville poet's additions, these became books IV, V, VII, VIII, and IX. There are unique details in Gilo's work that suggest that he had access to eyewitnesses.