Why does Shakespeare portray Duncan as an elderly, respected king when the real Duncan was actually a younger, weak man?

Shakespeare's portrayal of King Duncan was different in the play than from the reality as he deliberately mixed the facts with fiction.

Explanation:

It is noteworthy that the play 'Macbeth' was written by William Shakespeare in sometime between 1603-1607, some 400 years ago after the real incidents. Macbeth was the King of Scotland from 1040 – 1057.

The play 'Macbeth' was not written as a historical play rather a play for amusement of King James I. This is the reason that Shakespeare deliberately mixed facts of past realities with fiction. Though King Duncan was weak and inadequate ruler of Scotland in the past, Shakespeare mixed the element of fiction and turned the character of King Duncan into old and wise King.

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