Amleth

According to the chief medieval authority, Saxo Grammaticus' Gesta Danorum, Amleth is the son of Horvendill (Gervendill) and Gerutha. After Horvendill is murdered by his brother Feng, Feng marries Gerutha; the young Amleth, fearing for his life, deliberately pretends to be an imbecile to allay suspicion. Saxo recounts episodes in which Feng tests Amleth, plots against him, and sends him to Britain with attendants bearing written instructions for his death; Amleth secretly alters those wooden tablets so the British king slays the attendants and gives Amleth his daughter in marriage. He accumulates wealth abroad and ultimately returns to Denmark as part of the narrative arc of vengeance against Feng. Later medieval Icelandic and vernacular treatments preserve and adapt these motifs, and the cycle entered wider European literary transmission that influenced tales such as Havelok and, in early modern reception, Shakespeare's Hamlet.

Medieval sources concentrate on Amleth's actions and role rather than a fixed physical portrait; Saxo presents him as a young Danish prince (son of Horvendill) whose outward demeanour is that of a fool while secretly concealing cunning. The texts provide little consistent description of clothing or stature. Later cultural treatments—romantic dramas, modern films (for example The Northman), and stage portrayals—represent him visually as a Viking-age youth or warrior-prince, but these are adaptations rather than primary medieval depictions.

Amleth's 'abilities' are narrative traits and skills: deliberate feigning of madness as a strategy for survival; acute cunning and resourcefulness in anticipating and thwarting plots (e.g., responding to Feng's tests and neutralizing an eavesdropper); forgery/diplomacy in secretly altering the attendants' wooden tablets to secure marriage in Britain; the covert accumulation and concealment of wealth abroad; and the persistent motive of calculated vengeance against his uncle. These are described in Saxo's account and later summaries rather than framed as supernatural powers.