John Lydgate, Benedictine monk and prolific author of Middle English poetry, finished writing The Siege of Thebes in the early 1420s. An apocryphal Canterbury Tale, The Siege is Lydgate’s counterpart to Chaucer’s The Knight’s Tale and remains the only extant Middle English retelling of the struggle between Oedipus’s sons. Across its four parts, The Siege unfolds the aftermath of a paternal curse and the conflict between two brothers, Eteocles and Polynices, over their father’s throne. As the follow-up to Lydgate’s Troy Book, The Siege adopts some of the moralizing practices of that earlier text, as well as interrogating issues of poetic authority. It is Lydgate’s most political poem and boasts a lasting influence on Caxton’s printed edition of The Historie of Jason. This edition, based on MS Arundel 119, presents readers with an accessible approach to The Siege of Thebes.