[1] E. B. Everitt, Eric Sams, and Peter Ackroyd have argued that this play is perhaps Shakespeare's first drama.
His appendix notes correlations of images and ideas that are found only in Shakespeare's plays and not from any known playwright of the era, such as serpents stinging via their tongues and reporting of Judas Iscariot saying "all hail," which is non-Biblical, but also found in such plays as Henry VI, Part 3.
Edmund Ironside tells the story of a battle between two men who both want to be king of England: Edmund Ironside, who is a native, and depicted as noble, and Canutus (based on Cnut the Great), who is a Danish prince, and depicted as treacherous.
A third important figure is Edricus (based on Eadric Streona), who is duplicitous, plays each side against the other, and who also wants the crown.
Edricus is occasionally found alone on stage, and frequently boasts about his villainy (in a manner similar to the protagonist of Shakespeare's Richard III).
Their mother discloses that Edricus was in fact born the bastard child of a soldier she once met.
Edricus calls her a witch, and says that Stitch can enter his service, but first he must banish their parents from town.
Canutus, angry that two of his supporters have deserted him on the day of his wedding to Southampton's daughter, Egina, decides to get revenge on them by cutting off the hands and noses of their sons.
Stitch, now dressed in aristocratic clothing, has a scene where he play-acts the part, and is a Falstaffian comic tyrant.
In the letter Edricus claims that he defected because of rumors that Ironside was hunting for him, and he begs for mercy.
Meanwhile, as the Danes are ravaging the country, Emma, the stepmother of Ironside, says goodbye to her two young sons Alfred and Edward, who are about to embark and find safety with her brother, Duke Richard of Normandy.