Shakespeare's Macbeth remains one of his most popular plays, both for classroom study and performance, and with good reason. Here we have the playwright's shortest play, but arguably his most intense, in terms both of its action and its portrayal of human relationships. The "butcher and his fiend-like queen" are among the most attractive villains in stage history, and the profound psychology with which Shakespeare imbues them is deliciously pleasurable for theater audience and student alike.
Macbeth was a real king of eleventh-century Scotland, whose history Shakespeare had read in several sources, principally the Chronicles of Holinshed, to which he referred for many of his other historical dramas. In Holinshed's account, Banquo and Macbeth combine to kill King Duncan after winning his favor in a battle against the Danes. The original story is full of wonderful details that show the cunning of the Scots and Macbeth, who slaughtered an entire Danish army not by brute force, but by cunning: first mixing a sleeping potion and sending it, like the Trojan horse, as a gift to the enemy army. Once they were asleep, Macbeth was able to kill them easily. Presumably from this incident, Shakespeare derived his idea of having Lady Macbeth administer a sleeping potion to the guards of King Duncan's chamber.
In Holinshed's account, however, although we learn that Macbeth's wife is ambitious to become queen, Lady Macbeth does not feature as an accomplice. Instead, Banquo joins forces with Macbeth in killing Duncan. As we shall see later, this particular confederacy of murderers presented Shakespeare with a problem.
