Hoping to win back the thirteen colonies, Parliament in 1778 relinquished its power over internal taxation and regulation and gave the Carlisle Peace Commission wide discretion to suspend British policies in order to negotiate a truce. Because the Continental Congress consistently rejected these peace offerings and achieved independence, few historians have given serious attention to the interaction between Congress and the Commissioners. This article argues that the process of rejecting the Commission’s gestures marked an important watershed in the conceptualization of congressional power and national unity. Congress donned a public face of confidence and unanimity even as its leadership worried about dissent and disloyalty. This tension mirrored the paradoxes of American sovereignty, touted in terms of high principle and consent, but secured through force and diplomatic opportunism. The timing of the offers, after Saratoga and during negotiations for a French alliance, only highlighted the peculiarities of American sovereignty, which claimed command over as well as deference to the states. As the months passed, Congress and the Commissioners engaged in an argument over their authority to rule, exposing contradictions in their governing logic, and resorted increasingly to desperate appeals to the individual states and to shows of force to maintain mastery over the continent. Occurring at a unique moment in the reconciliation of the paradoxes of imperial sovereignty, Congress’s response to the Commission deserves a special place in the history of the U.S. nation-state’s formation.