SOURCE: Mabillard, Amanda. “Sources for The Merchant of Venice.” Shakespeare Online, 2000. http://www.shakespeare-online.com

In the following essay, Mabillard explores Shakespeare's use of the Gesta Romanorum as the basis of the three caskets motif in The Merchant of Venice.

There are many possible texts that Shakespeare could have used in constructing The Merchant of Venice, and while we can confirm that he relied upon two particular sources, the others sources I will mention were likely, though not definitely, influences on Shakespeare. His chief source was a tale in an Italian collection entitled Il Pecorone or The Simpleton, written in 1378 by Giovanni Fiorentino, and published in 1565. No known English translation existed for Shakespeare to use, but it is possible, although—very unlikely, that someone Shakespeare knew had translated his own private copy and gave it to Shakespeare to read. It is more likely that Shakespeare was more learned...