The Battle of Camlann is the legendary final battle of King Arthur, in which Arthur either died or was fatally wounded while fighting either alongside or against Mordred, who also perished. The original legend of Camlann, inspired by a purportedly historical event said to have taken place in the early 6th-century Britain, is only vaguely described in several medieval Welsh texts dating from around the 10th century. The battle's much more detailed depictions have emerged since the 12th century, generally based on that of a catastrophic conflict described in the pseudo-chronicle Historia Regum Britanniae. The further greatly embellished variants originate from the later French chivalric romance tradition, in which it became known as the Battle of Salisbury, and include the 15th-century telling in Le Morte d'Arthur that remains popular today.

King Arthur, according to legends, was a king of Britain. He is a folk hero and a central figure in the medieval literary tradition known as the Matter of Britain.