King Lear is a tragedy written by William Shakespeare. It is loosely based on the mythological Leir of Britain. King Lear, in preparation for his old age, divides his power and land between his daughters Goneril and Regan, who pay homage to gain favour, feigning love. The King's third daughter, Cordelia, is offered a third of his kingdom also, but refuses to be insincere in her praise and affection. She instead offers the respect of a daughter and is disowned by Lear who seeks flattery. Regan and Goneril subsequently break promises to host Lear and his entourage, so he opts to become homeless and destitute, goes insane, and the French King married to Cordelia invades Britain to restore order and Lear's rule. In a subplot, Edmund, the illegitimate son of Gloucester, betrays his brother and father. Tragically, Lear, Cordelia and several other main characters die.

Shakespearean tragedy is the designation given to most tragedies written by playwright William Shakespeare. Many of his history plays share the qualifiers of a Shakespearean tragedy, but because they are based on real figures throughout the history of England, they were classified as "histories" in the First Folio. The Roman tragedies—Julius Caesar, Antony and Cleopatra and Coriolanus—are also based on historical figures, but because their sources were foreign and ancient, they are almost always classified as tragedies rather than histories. Shakespeare's romances were written late in his career and published originally as either tragedy or comedy. They share some elements of tragedy, insofar as they feature a high-status central character, but they end happily like Shakespearean comedies. Almost three centuries after Shakespeare's death, the scholar F. S. Boas also coined a fifth category, the "problem play," for plays that do not fit neatly into a single classification because of their subject matter, setting, or ending. Scholars continue to disagree on how to categorize some Shakespearean plays.