Did You Know?
The historical Macbeth (c.1005-1057) was king of Scotland from 1040 to 1057. His wife was Lady Gruoch, a granddaughter of Scottish king Kenneth III and formerly the wife of Gilcomgain, Thane of Moray. After Gilcomgain's death in battle, during a revolt against Duncan, Gruoch fled to the neighbouring county of Ross with her son, Lulach. Macbeth, Thane of Ross, became her protector and, in 1035, her second husband.
Although Shakespeare portrays Duncan as an elderly man, he was actually under 40 when he was killed - in battle, not in bed - by Macbeth. His sons Malcolm and Donald Bane were less than 10 years old at the time.
Macbeth, who reigned for 17 years, was by all reports a good king: under his rule, Scotland prospered and was relatively peaceful until a failed invasion by the Northumbrians in 1053. In 1057, Duncan's son Malcolm Canmore, now a grown man, returned to Scotland and killed Macbeth in a battle in Aberdeenshire - nowhere near Dunsinane or Birnam Wood. Assuming the throne as Malcolm III, he died in 1093.
Shakespeare would have seen no reason to question the traditional belief that Banquo's son, Fleance, fled to Wales, where he married a daughter of the Welsh king, and that their son returned to Scotland to become the founder of the Stuart royal line. There is no historical evidence however, that Banquo or Fleance actually existed.
If, as seems reasonable to suppose, Shakespeare wrote Macbeth in the hopes of pleasing James I (formerly James VI of Scotland) - who was a patron of Shakespeare's company and had doubled the fee they received for court performances - the attempt misfired. Perhaps upset by its depictions of the assassination of a Scottish king and of witches influencing human destiny, James banned Macbeth for five years. It was produced only once more during Shakespeare's lifetime: in 1611 at the Globe Theatre, which burned to the ground shortly afterwards, destroying all sets, props, costumes and manuscripts - which may be another origin of the play's reputation for ill luck.