The correspondence and diaries of two American merchant sailors, James Cathcart and Captain Richard O'Brien, who were held captive in Algiers from 1785 to 1795–96, bridge and complicate the two literatures of commercial-diplomatic and informal networks. During this period, the nascent American government and over one hundred of its citizens were held hostage by the North African "Barbary States" of Algiers, Morocco, Tripoli, and Tunis. Using the letters and diaries of the two most prolific captives, Cathcart and O'Brien, this article shows that the captives successfully penetrated diplomatic networks and the minds of sympathetic diplomats such as David Humphreys, who exploited the captives' plight to help his own longstanding campaign of fostering national identity. The captives similarly deployed the pragmatic skills and style of correspondence they learned as merchant sailors to self-interestedly weave their cause for liberty into the emerging national narrative. These interventions echoed the sentiments and rhetoric of participants in Shays's Rebellion (Massachusetts, 1786–87) and the Whiskey Rebellion (western Pennsylvania, 1791–94). Yet perhaps because of the very different (and, in fact, conflicting) goals of American captives in Algiers and rebels in rural Massachusetts and Pennsylvania, the ever-increasing scholarship on American captives in Barbary has overlooked how these nonelite citizens' campaigns were intertwined. Their shared political rhetoric and notions of national identity were developed and deployed thousands of miles apart, likely thanks to their shared backgrounds in self-interested participation in the revolution and the captives' ready access to newspapers and personal correspondence that kept them informed of domestic crises on the American frontier. Literary analysis of American captives in Barbary is typically juxtaposed with Indian captivity narratives, which is especially applicable to fictional Barbary narratives, and a much smaller number of published nonfictional accounts. The comparison does not hold for the more abundant short-form correspondence, which represents a more significant and untapped opportunity for scholarly analysis of the epistolary styles of the two most prominent American captives in Algiers, who echoed and engaged with the rhetoric and ideas of rebels on the young nation's terrestrial frontier as they were being held captive on the maritime frontier. This article argues that, through the captives' political rhetoric and canny exploitation of their positions in informal transnational networks, we can gain new insights into how nonelite citizens, whether in rural Massachusetts, Pennsylvania, or Algiers, drew on a shared language of liberty and expectations of popular participation in policy development to simultaneously influence the terms of national identity and reinvent themselves.