Date

Macbeth cannot be precisely dated, but the play features many compliments to King James VI/I suggesting the original writing is Jacobean rather than Elizabethan. The procession of Kings in Act Four could date the composition to be around 1603 – the year James Stuart ascended the English throne – and celebrates his ancestors (James traced his lineage to Banquo). References to 'equivocation' by the Porter in Act Two and other allusions are seen to be references to the trial of the Gunpowder Plot conspirators which took place in January – March 1606. 

An eyewitness account by Dr Simon Forman dates the first public performance of Macbeth at the outdoor Globe Theatre in April 1611, though it was most likely performed at Court before King James in August or December 1606. 

The 1623 First Folio is the only early printed text and its brevity suggests theatrical editing and revision, possibly by Thomas Middleton. In particular, the scenes involving Hecate seem to be additions made by Middleton and are similar to scenes in his tragicomedy The Witch.

Sources

Shakespeare borrowed heavily from Raphael Holinshed's Chronicles of England, Scotland and Ireland (1587), a popular history well known to Shakespeare and his contemporaries (Shakespeare had previously used Holinshed for his English History plays). Macbeth is based on the account of the reigns of Duncan and Macbeth in The Chronicles of Scotland, though with some notable differences. For example, in Chronicles, Banquo is Macbeth's accomplice in the plot to overthrow King Duncan. However, in Macbeth, Shakespeare recasts Banquo and his descendants as Macbeth's adversaries, undoubtedly to please the present King James (to portray the King's ancestor as a murderer would have been risky).