xiv, 479 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / My dissertation examines the ethical engagement of political invective poetry in thirteenth- and fourteenth-century Italy. Modern criticism tends to treat medieval invective as a playfully subversive but marginal poetic game with minimal ethical weight. Instead, I aim to restore these poetic productions to their original context: the history, law, and custom of Tuscan cities. This contexts allows me to explore how humor and fury, in the denunciation of political enemies, interact to establish not a game but an ethics of invective. I treat ethics as both theoretical and practical, referring to Aristotle, Cicero, and Brunetto Latini, and define ethics as the pursuit of the common good in a defined community. Chapter I introduces the corpus, its historical and cultural background, its critical reception, and my approach. Chapter II discusses medieval invective in Tuscany and surveys the cultural practice of invective writing. Chapter III approaches invectives written by Rustico Filippi during the Guelph and Ghibelline wars. Chapter IV explores invectives by Cecco Angiolieri set in Siena, which polemicize with the Sienese government and citizenry. Chapter V examines invectives in Dante's Commedia (Inf. 19, Purg. 6, and Par. 27), focusing on his unexpected humor and his critique of the papacy, the empire, and Italian city governments. My conclusion examines the ethical function of slanderous wit in wartime invective. These poems balance verbal aggression with humor, claiming a role for laughter in creating dialogue within conflict. Far from a stylistic or ludic exercise, each invective shows the poet's activism and ethical engagement. This dissertation includes previously published material. / Committee in Charge: Regina Psaki, Chairperson, Romance Languages; Massimo Lollini, Member, Romance Languages; David Wacks, Member, Romance Languages; Steven Shankman, Outside Member, English