Geoffrey Chaucer's Troilus and Criseyde is a literary feat, combining genres of romance, tragedy, and even comedy into one poetic work that greatly entertained and moved medieval readers. Chaucer, however, can't take full credit for the subject matter of his story; the character of Troilus made a peripheral appearance in earlier texts, as far back as Homer's Iliad and Virgil's Aeneid. Troilus is also mentioned as a Trojan warrior in the sixth-century Latin book De excidio Troiae historia (The Fall of Troy, A History) by Dares Phrygius. The character of Criseyde is first featured (as "Briseida") in the twelth-century French romance, Le Roman de Troie (The Romance of Troy) by Benoît de Sainte-Maure. Literary critics have stated how Chaucer was unequivocally inspired by these works to pen his own Troilus and Criseyde.
It was the Italian writer Giovanni Boccaccio who first transformed the narrative of the Trojan lovers into a more fleshed-out romance, as a lengthy narrative called Il Filostrato, or The One Overwhelmed by Love. Chaucer expanded the story even more deeply, adding many original plot twists and characterization that differs from older texts. There are many differences between the two authors' versions; Pandarus in Boccacio's Troilus is the cousin, not the uncle of Criseyde; Chaucer focuses much more on the romance of the lovers, while Boccaccio emphasizes their downfall; Boccacio divides the drama into eighth cantos as opposed to Chaucer's five books. Yet literary critics, such as Barry Windeatt, have taken note that both Boccaccio and Chaucer's renditions share a common tone and tendency to include "quasi-dramatic exchange of dialogue and lyrical expression in soliloquies." Furthermore, both impart a similar theme: the peril and illusion of worldly love.
Chaucer's Troilus stands today not as the author's most famous work, yet at the time it was published, it made its mark on Chaucer's audience. This is perhaps due to the fact that previous variations of the tale, such as Boccacio's, were little-known in that era, thus giving it "more novelty in an account of the whole love affair from beginning to end," according to Windeatt. And Chaucer's work certainly created enough of an impact to inspire William Shakespeare, over two centuries later, to produce his own version of the story, as his play Troilus and Cressida.