Boccaccio's Decameron: an Early Printed Copy.

The Decameron is a collection of 100 novellas by Italian author Giovanni Boccaccio, probably begun in 1350 and finished in 1353. It is a work best known for its bawdy tales of love, appearing in all its possibilities from the erotic to the tragic. Among Shakespeare scripts with analogies in the Decameron are the following:

(1) The main source for All's Well is the story of Giletta de Nerbone in the thirty-eighth tale in Painter's Palace of Pleasure, the ninth story of the third day in The Decameron

(2) Posthumus's wager on Imogen's chastity in Cymbeline was taken by Shakespeare from an English translation of a fifteenth century German tale, "Frederyke of Jennen", whose basic plot came from tale II, 9.

(3) The motif of the three caskets in The Merchant of Venice by Shakespeare is found in tale X, 1. However, both Shakespeare and Boccaccio probably came upon the tale in Gesta Romanorum.

Picture and data courtesy of the Yorck Project, under Creative Commons Attribution-ShareAlike License (Wikipedia).