This article investigates how early modern migrants articulated identification with their host society in the context of the late eighteenth-century Dutch Republic, a period preceding modern nationalism. Drawing on a unique dataset derived from the Prize Papers – a collection of testimonies from captured sailors interrogated by British Admiralty courts – we analyze migrants’ declarations of sovereign allegiance. We assess how factors such as duration of residence, local citizenship (poorterschap), occupational rank, and marital status influenced migrants’ identification with their adopted polity. Using logistic regression, we find that civic institutional embeddedness, reflected in city citizenship, and occupational rank, especially among ship captains, significantly predicted identification with the Dutch Republic. In contrast, duration of residence and marital status had weak and statistically insignificant effects. Our findings highlight that pre-national forms of identification were deeply embedded in civic and institutional contexts rather than simply reflecting modern nationalist sentiments. By combining quantitative analysis with targeted archival research into individual biographies, this study demonstrates the complex interplay between institutional opportunities and personal networks in shaping migrants’ allegiances, thereby offering a nuanced historical perspective relevant to contemporary debates on civic integration.