King Lear is one of Shakespeare’s greatest tragedies; indeed, some critics have considered it the greatest. It is certainly one of the bleakest. The plot and subplot deftly weave together the principal themes of the play, which include reason, madness, blindness of various kinds, and – perhaps most crucially of all – the relationship between a father and his children. Before we offer some words of analysis of King Lear, it might be worth recapping the plot of the play.
King Lear: plot summary
King Lear has a plot and subplot which neatly and closely complement each other. The main plot centres on the ageing King Lear, who begins the play by dividing up his kingdom between his three daughters, only to disinherit one of them, Cordelia, when she refuses to tell him that she loves him. The subplot also focuses on a father, the Duke of Gloucester, who has two sons: Edgar, his legitimate heir; and Edmund, his illegitimate son whom he fathered during a moment of youthful lust.
When Lear gathers his three daughters together to divide up his realm among them, he gives Regan (who is cold and calculating) and Goneril (who is hot-headed and impetuous) the biggest share, because they both play along with his game when he asks his daughters to say which of them loves him most. But Cordelia, the third daughter (who is staid and dignified) refuses to play this game and says she merely loves him as much as is expected of a daughter for her father, and as a result of her refusal, King Lear banishes her to France. When the Earl of Kent tries to reason with Lear, he, too, is banished – but he returns, in disguise, so he can remain close to his King and serve him.
Meanwhile, in the subplot, Edmund, the illegitimate son of the Earl of Gloucester, sets about getting his half-brother Edgar out of the way by telling their father that Edgar plans to murder him. In an echo of the main plot, Gloucester banishes his (true and loyal) son, Edgar, who will turn up shortly after this, in disguise, as a beggar and madman going by the name of ‘Poor Tom’.
No sooner have they been given Lear’s kingdom than his remaining two daughters start turning against their aged father. They refuse to let his vast royal entourage into their home, and Lear – complete with his Fool (who is the one person who can speak the truth to the King 
without suffering punishment), and with Kent (in disguise) – walks out into a storm. Sheltering in a hut, the three of them meet ‘Poor Tom’ (Edgar in disguise).
Gloucester takes Lear into his home, and Lear curses his daughters for not loving him. Gloucester knows that Regan and Cordelia plan to kill their father, so he sends Lear to Dover, on the coast, where Cordelia is landing with a French army. Edmund tells Regan and her husband, the Duke of Cornwall, what Gloucester has done, and they put out Gloucester’s eyes and cast him out. Edgar (still disguised as the lunatic Poor Tom) meets his father, and madman leads blind man to Dover, where he dissuades Gloucester from suicide. They meet Lear, who has now gone completely mad and is wandering the heath.
As if this isn’t enough plot strands involving this rather large cast of central characters, there is also a love triangle between the two sisters, Regan and Goneril, and Edmund, whom they both love (even though they are both already married). Edgar intercepts a love letter Goneril has written to Edmund, and passes it to Goneril’s husband, Albany. When Albany gets back from fighting Cordelia’s French force, he challenges Edmund to fight anyone who challenges him; Edgar ends up killing his half-brother. As Edmund dies, he reveals that he has arranged for Lear and Cordelia to be killed.
Everything now descends into mass death, but also enlightenment: Goneril poisons Regan over Edmund, and then kills herself. Lear finds Cordelia in prison, following her capture; she dies in his arms, and Lear, having wept for her, dies.
King Lear: analysis
King Lear is a bleak play, but like all great tragedies, a measure of catharsis or healing is achieved through Lear’s suffering, as well as that of the other characters. The play might be summed up as a battle between reason and madness, or between blindness and sight, except that the conflict between the two dissolves into a distinction without a difference. Paradoxically, it is only when he has been (literally) blinded that Gloucester gains insight into his family, and realises that Edgar, not Edmund, was his true and trusted son. Similarly, it is only when King Lear has gone completely mad on the heath that he comes to realise that Cordelia, not Regan or Cordelia, loved him best; in comparison, his other two daughters were mere flatterers using him to get his kingdom (and then push him out of the way).
These paradoxes are also present in the relationship between King and Fool: Lear’s folly or (metaphorical) blindness is highlighted by his Fool, who is one of the wisest people in all of King Lear, and can (paradoxically, again) only be so frank with his King because, being a mere Fool, nobody is expected to take him seriously. Part of the artistic triumph of the play is the way Shakespeare brings all of these apparent contradictions together to create a piece of compelling drama that is moving without being sentimental, despairing but also illuminating. Thematically, these various strands work together to reinforce the play’s central concern with madness and reason, blindness and seeing.
And Shakespeare cleverly sets up the characters as doubles, opposites, and complements: as Harold Bloom notes in a persuasive analysis of King Lear (in his book Shakespeare: The Invention Of The Human), in a play where so many of the major characters speak to each other at some point, it was canny of Shakespeare never to have Lear and Edmund speak a word to each other throughout the entire play, because they are complete antitheses: where Lear is all feeling, Edmund is ‘ice-cold’ and emotionless.
Less than a hundred years after Shakespeare wrote the play, in the 1680s, King Lear was given a rather dramatic (as it were) rewrite by the Poet Laureate, Nahum Tate. But in fact the story of King Lear was originally a happy one, when it first appeared in the chronicles of Geoffrey of Monmouth in the twelfth century. The anonymous play, King Leir, on which Shakespeare based his tragedy also ends on a somewhat more upbeat note. Shakespeare took the story and unleashed its apocalyptic tragedy, in which everyone dies except Edgar, who is to inherit the realm whose division, at the outset, led to the subsequent chaos that unfolded.
One reason Shakespeare may have been tempted to take King Leir and rewrite it for the Jacobean stage was that his King, James I of England (and James VI of Scotland), had been responsible for uniting England and Scotland under a common ruler; indeed, if we include Wales (which always gets left out), he brought together three kingdoms. In this connection, Lear’s fatal decision to divide his kingdom into three parts at the beginning of King Lear takes on additional historical relevance. Was Shakespeare trying to flatter his King and show him How Not to Rule?