Fleance is Banquo’s son. After Macbeth sends murderers after Banquo and Fleance, Banquo fights off the murderers while Fleance flees. In Shakespeare’s source material, the legendary semi-historical accounts of the Holinshed Chronicles, Fleance eventually goes on to sire a son who returns to Scotland and begins the Stuart line of monarchs. King James I of England, Shakespeare’s patron, was a Stuart, and many scholars have speculated that the the play’s gracious portrayal of Banquo was meant to flatter the king.

Ross is a Scottish thane who serves as a messenger throughout the play. Ross first appears in act I, scene II, when he reports to Duncan about Macbeth and Banquo’s victory over the Norwegian forces. He later defects to Malcolm’s cause after it becomes increasingly clear that Macbeth is a tyrant. Ross’s role as a messenger is often used to introduce information about events that happen offstage, such as when he reports about the deaths of Macduff’s family and Young Siward.

Donalbain is Duncan’s younger son and Malcolm’s brother. After his father’s murder, he flees to Ireland, hoping that separating from his brother will safeguard him. Macbeth spreads the rumor that Malcolm and Donalbain were responsible for their father’s death, using their hasty escape as evidence of their guilt.

In ancient Greek mythology, Hecate is the goddess of witchcraft. She is presented as the queen of the witches, and she chastises the three “weird sisters” for speaking to Macbeth without her. The three weird sisters seem to fear Hecate, remarking nervously about her “angerly” expression and hastening to do what she asks. Hecate devises the plan to lull Macbeth into a false sense of security by issuing misleading prophecies in act IV, scene I, claiming that “security is mortals’ chiefest enemy.” 

There is controversy surrounding whether Hecate was included in the original manuscript of the play or whether she was added in a later edition. Some Shakespearean scholars believe that a different poet is responsible for the scenes featuring Hecate, citing their incongruous tone and verse structure as evidence.

Siward is the English Earl of Northumberland and Malcolm’s uncle. He leads the army that Malcolm uses to reclaim Scotland from Macbeth. Siward is a stoic man who values honor and courage. When he hears that his son died in battle, his primary concern is whether his son died an honorable death. When he hears that his son’s wounds were on his front rather than on his back, he says that he could not “wish [Young Siward] to a fairer death” and refuses to mourn him further.

The Doctor is called in to assess Lady Macbeth’s sleepwalking. Upon hearing her talk in her sleep, he becomes convinced that her malady is not physical, but spiritual. He suggests that the only cure for what ails Lady Macbeth, and Macbeth himself, is to confess to a priest.

Lady Macduff is Macduff’s wife. She loves her children and is not afraid to challenge her husband’s decisions, which is evident when she criticizes Macduff’s decision to flee to England. After the witches tell Macbeth to fear Macduff, Macbeth sends murderers to Macduff’s home. The murderers kill Lady Macduff and all of her children, which gives Macduff great grief when he hears the news in England.

Lady Macduff is most often read as a foil for Lady Macbeth due to her status as a loving wife and mother. Though she is outspokenly critical of her husband’s decisions, she does not mock him or insult him. She also worries for herself and her children in Macduff’s absence, highlighting her compassion and sensibility. In addition to foiling Lady Macbeth, Lady Macduff’s murder is also used to reinforced Macbeth’s villainy and descent into true tyranny.  

Lennox, Menteith, Angus, and Caithness are Scottish thanes who desert Macbeth when Malcolm’s forces arrive. Lennox begins the play in the company of King Duncan and is an insecure statesman. However, after Duncan’s death and Macbeth’s ascension, he quickly becomes suspicious. In act III, scene, VI, Lennox indicates his support for Malcolm and Macduff’s plan, noting all of the “strangely borne” events around Scotland. The desertion of Lennox and the other Scottish lords emphasizes just how poor of a ruler Macbeth is.

The three murderers are hired by Macbeth to kill Banquo and Fleance. They were originally angry with Macbeth, but Macbeth convinces them that Banquo is the true cause of their misfortune. They successfully murder Banquo, but Fleance escapes, leaving open the possibility that the witches’ prophecies will come true.