From 1580 to 1700, low-ranking Spanish imperial officials ceaselessly moved across the Spanish empire, and in the process forged a single coherent political unit out of multiple heterogeneous territories, creating the earliest global empire. Global Servants of the Spanish King follows officials as they itinerated between the Americas, Asia, Europe, and Africa, revealing how their myriad experiences of service to the king across a variety of locales impacted the governance of the empire, and was an essential mechanism of imperial stability and integration. Departing from traditional studies which focus on high-ranking officials and are bounded by the nation-state, Adolfo Polo y La Borda centers on officials with local political and administrative duties such as governors and magistrates, who interacted daily with the crown's subjects across the whole empire, and in the process uncovers a version of cosmopolitanism concealed in conventional narratives.