Macbeth is a tragedy by William Shakespeare. It is thought to have been first performed in 1606. It dramatizes the damaging physical and psychological effects of political ambition on those who seek power. A brave Scottish general named Macbeth receives a prophecy from a trio of witches that one day he will become King of Scotland. Consumed by ambition and spurred to action by his wife, Macbeth murders King Duncan and takes the Scottish throne for himself. A Scottish noble and an initially valiant military man, Macbeth, after a supernatural prophecy and the urging of his wife, Lady Macbeth, commits regicide, usurping the kingship of Scotland. He thereafter lives in anxiety and fear, unable to rest or to trust his nobles.