In Forged in the Shadow of Mars, Peter W. Sposato traces chivalry's powerful influence on the mentalitè and behavior of a sizeable segment of the elite in late medieval Florence. He finds that the strenuous knights and men-at-arms of the Florentine chivalric elite—a cultural community comprised of men from both traditional and newly emerged elite lineages—embraced a chivalric ideology that was fundamentally martial and violent. Chivalry helped to shape a common identity among these men based on the profession of arms and the ready use of violence against both their peers and those they perceived to be their social inferiors. This violence, often transgressive in nature, was not only crucial to asserting and defending personal, familial, and corporate honor, but was also inherently praiseworthy. In this way, Sposato highlights the sharp differences between chivalry and the more familiar civic ideology of the popolo grasso, the Florentine mercantile and banking elite who came to dominate Florence politically and economically during the thirteenth and fourteenth centuries.

As a result, in Forged in the Shadow of Mars, Sposato challenges the traditional scholarly view of chivalry as foreign to the social and cultural landscape of Florence and contests its reputation as a civilizing force. By reexamining the connection between chivalric literature and actual practice and identity formation among historical knights and men-at-arms, he likewise provides an important corrective to assumptions about the nature of elite violence and identity in medieval Italian cities.