Postal Intelligence connects and situates histories of the post and government intelligence alongside print technology and state power in the wider context of the early modern communications revolution. In the sixteenth century, postal services became central to domestic governance and foreign policy enterprises, extended government reach and surveillance, and offered new control over the public sphere. Rachel Midura focuses on the Tassis family, members of which served as official postmasters to the dukes of Milan, the pope, Spanish kings, and Holy Roman emperors. Using administrative records and family correspondence, she follows the Tassis family, their agents, and their rivals as their influence expanded from northern Italy across Europe. Postal Intelligence shows how postmasters and postmistresses were key players in early modern diplomacy, commerce, and journalism, whose ultimate success depended on both administrative ingenuity and strategic ambiguity.