In the small Italian town of Udine on the first day of carnival - February 27, 1511 - a crowd of Udinesi and peasants gathered for the festivities, along with more than 1000 tired, hungry militiamen. The wine flowed, looting began, and the bloody rioting that ensued soon spread to the surrounding countryside. By the time it was over, nobles had been slaughtered and their castles looted or destroyed, bodies were dismembered and corpses fed to animals, and the Udine carnival massacre had become the most extensive and damaging popular revolt in Renaissance Italy. Mad Blood Stirring is an account and analysis of that event, as well as the social structures and historical conflicts preceeding it and the subtle shifts in the mentality of revenge it introduced. Uncovering the many reciprocal connections between the carnival motifs, hunting practices and vendetta rituals - all of which tested the boundaries between the humane and the bestial - Muir finds that the massacre occurred because, at that point in Renaissance history, violent revenge and allegiance to factions provided the best alternative to failed political institutions. Friulan contemporaries used the terminology of revenge to explain what had happened in their society: Hot blood stirred, red blood spilled and common blood of kinship was shared. But the carnival massacre, Muir argues, marked a crossroads: the old mentality of vendetta as an appropriate stirring of mad blood was soon to be supplanted by the emerging sense that the direct expression of anger should be suppressed and vendettas replaced by duels. While vendettas still governed, however, the strife of Friuli clearly dramatized the fragile relationships between the political center and its periphery, the tenuous nature of patronage relationships, and the inherent ambiguity of revenge obligations.