In Shakespeare’s play ‘Macbeth’, Macbeth became the king of-

Macbeth, tragedy in five acts by William Shakespeare, written sometime in 1606–07 and published in the First Folio of 1623 from a playbook or a transcript of one.
Macbeth and Banquo, who are generals serving King Duncan of Scotland.
Later, Macbeth became the king of Scotland.

Important characters:
Macbeth, Lady Macbeth, Duncan, Banquo, Three Witches.

Source: Britannica.com