The mid-thirteenth-century theorist and rhetorician Brunetto Latini proposed a vigorous republican account of the art of government and the nature of community in his encyclopedic treatise, Li Livres dou Tresor . The interpretation of Latini's republicanism has been heavily based on its literary sensibilities, its attachment to rhetoric, and its praise for classical civic virtues. But Latini deserves to be classified as a republican insofar as he founds social and political order upon commercial principles—the production and exchange of material goods for profit—and consequent economic defense of republican government. Hence, the example of Latini challenges one of the principal remaining barriers that supposedly separates medieval defenses of republicanism from Renaissance versions. The essay contends that Latini holds that self-governing institutions depend upon and are especially well suited to sustain a society whose conception of the common good includes the creation and exchange of those material necessities required for physical welfare and comfort.