The Alliterative Morte Arthur is a poem of 4,346 lines, that belongs to the tradition of the alliterative revival of fourteenth-century England. The form of alliteration had been widely used in Old English poetry. The Alliterative Morte Arthur uses the unrhymed alliterative long line which falls into two half-lines and is connected by the alliteration of stressed syllables. It was composed around the year 1400 but its author is unknown to us.
The poem is clearly structured and can be divided into four parts. First emissaries from the Roman emperor Lucius arrive at King Arthur's court at Carlisle. They demand Arthur to pay tribute to Lucius, who defies the Roman emperor which results in war. Arthur leaves for France and during his absence Mordred reigns in England. Having arrived in Brittany Arthur kills the giant of Mont St. Michel who holds the Duchess of Brittany as hostage. After a series of battles there is a final fight between the armies in which Lucius is killed, Arthur then sends the dead enemies back to Rome.
The third part is about the siege of Metz and the duel between Gawain and the Greek knight Priamus, who in the end befriends Gawain and joins the armies of King Arthur. At this very successful point of the campaign Arthur learns that Mordred has usurped the throne in England and has also taken his queen. Arthur wins a sea battle against Mordred's allies but in the ensuing fight at land Gawain and his men are killed. Arthur swears revenge and in a final huge battle Mordred is killed and Arthur mortally wounded and brought to Glastonbury where he is buried.
The poet uses a great amount of archaic vocabulary to describe the battles and fights. There was much discussion concerning the genre of the text, about the question if the wars waged by Arthur always have a just cause and if his actions are the depiction of the reign of a good king. Much indeed is open to interpretation.