The Duchy of Courland, a vassal of the Polish-Lithuanian Commonwealth in the Eastern Baltic, became a brief but unexpected colonial power in the mid-seventeenth century. The dukes of Courland attempted to engage in oceanic trade to improve their fortunes, establishing fortresses in the Caribbean and Western Africa. Histories of the Couronian colonial venture often focus on the figure of Duke Jakob Kettler as an inspired or overambitious innovator. Yet, embarking on such an enterprise required the utilisation of intricate networks stretching across oceans in a range of different contexts and locations. The study investigates the connections, entanglements and ruptures present in this remarkable example of early modern colonisation.