The Tragedy of King Lear is a tragedy by William Shakespeare. The title character descends into madness after foolishly disposing of his estate between two of his three daughters based on their flattery, bringing tragic consequences for all. The play is based on the legend of Leir of Britain, a mythological pre-Roman Celtic king. It has been widely adapted for the stage and motion pictures, and the role of Lear has been coveted and played by many of the world's most accomplished actors. The play was written between 1603 and 1606 and later revised. Shakespeare's earlier version, The True Chronicle of the History of the Life and Death of King Lear and His Three Daughters, was published in quarto in 1608. The Tragedy of King Lear, a more theatrical version, was included in the 1623 First Folio. Modern editors usually conflate the two, though some insist that each version has its individual integrity that should be preserved. After the Restoration, the play was often revised with a happy ending for audiences who disliked its dark and depressing tone, but since the 19th century Shakespeare's original version has been regarded as one of his supreme achievements. The tragedy is particularly noted for its probing observations on the nature of human suffering and kinship. George Bernard Shaw wrote, "No man will ever write a better tragedy than Lear".