Luigi da Porto adapted the story as Giulietta e Romeo and included it in his Historia novellamente ritrovata di due Nobili Amanti (Newly found tale of two Noble lovers) published in 1530.

Da Porto gave it much of its modern form, including the lovers' names, the rival families of Montecchi and Capuleti, and their location in Verona.

Da Porto presents his tale as historically true and claims it took place in the days of Bartolomeo II della Scala (a century earlier than Salernitano).

At the beginning of Act III, he enters looking for Romeo, only to create tensions with Mercutio, who was mocking Tybalt even before he walked into the scene.

Tybalt initially ignores Mercutio and confronts Romeo, who refuses to fight because of his recent secret marriage to Juliet.