This thesis presents a social history of the Irish community in La Rochelle from its settlement c. 1630 to its dispersal on the eve of the French Revolution in 1789. During the latter half of the seventeenth century, La Rochelle was the second most important port for Irish trade in France, after Saint-Malo. Throughout the eighteenth century, the city developed its economy through the Atlantic colonial trade, and alongside Nantes and Bordeaux, became a major centre of the trade of enslaved Africans. Dominated by a Protestant mercantile elite, La Rochelle might seem a surprising destination for an overwhelmingly Catholic Irish migrant population. Yet Irish migrants established a durable presence in the city, with several individuals — such as Richard Creagh, John Butler, and Denis MacCarthy — achieving economic success and social advancement. Combining a chronological and thematical structure, this thesis investigates the factors that contributed to the settlement, growth and decline of an Irish community in La Rochelle during the period c. 1630 to 1789. After settling in the 1630s, the Irish community expanded between the 1650s to the 1710s and integrated into French ancien régime society. From the 1740s, the community contracted and the migration virtually stopped by the 1760s. By 1789, the Irish presence in the city had largely dispersed. Employing a blended prosopographical and longitudinal approach, this study explores for the first time the history of the Irish men and women in La Rochelle. It analyses their migration, experiences of integration and their evolving perceptions of themselves. The thesis argues that migration to La Rochelle was a significant part of the phenomenon of Irish migration to continental Europe and must be interpreted within the broader context of early modern European mobility. Influenced by the processes of confessionalisation, state building and rise of capitalism, Irish migration was equally shaped by the internal dynamics of migration and migrants’ agency. This research therefore aims to make a significant contribution to the historiography of Irish migration to continental Europe during the early modern period.