The Draco Normannicus is a chronicle written circa 1167-1169 by Stephen of Rouen (Étienne de Rouen), a Norman Benedictine monk from Bec-Hellouin. The Draco (considered an epic by some critics, such as Irene Harris and Elizabeth Kuhl) was based largely on the work of Robert of Torigni and William of Jumièges Gesta Normannorum Ducum. The poem itself is unfinished, and also adapts parts of the Roman de Brut by Wace. Considered Stephen's principal work it survives in the Vatican Library. In the manuscript the poem runs to nearly 4,400 lines, though it has lost at least two passages, estimated at around one hundred verses each. The manuscript was initially anonymous, however it has been accepted for over one hundred years that Stephen is the undisputed author.