The story of Shakespeare's Hamlet was derived from the legend of Amleth, preserved by 13th-century chronicler Saxo Grammaticus in his Gesta Danorum, as subsequently retold by 16th-century scholar Francois de Belleforest. Shakespeare may also have drawn on an earlier (hypothetical) Elizabethan play known today as the Ur-Hamlet, though some scholars believe he himself wrote the Ur-Hamlet, later revising it to create the version of Hamlet we now have.

Romeo and Juliet belongs to a tradition of tragic romances stretching back to antiquity. The plot is based on an Italian tale translated into verse as The Tragical History of Romeus and Juliet by Arthur Brooke in 1562 and retold in prose in Palace of Pleasure by William Painter in 1567. Shakespeare borrowed heavily from both but expanded the plot by developing a number of supporting characters, particularly Mercutio and Paris.