Who married the mother of the Danish legendary figure Amleth?

Explanation

Amleth is a Danish legendary figure whose story is known from the chronicle of Saxo Grammaticus (Gesta Danorum). Prince Amleth's father, the king, was killed by his brother who seized power and married Amelth's mother. Amleth feigned madness to avoid suffering the same fate as his father. This material forms the basis of Shakespeare's Hamlet. It was also Shakespeare who situated the story in Elsinore.