This study is focused on Thomas Conolly of Castletown House, Co. Kildare, and the social networking of the power elite. Structured as a biography of Conolly, it acts as a prism through which to view the power of the ascendancy class in the second half of the nineteenth century. In this period the cultural hegemony of Ireland was dominated by the ascendancy class, which remained reasonably intact but was beginning to break down. At the heart of this class was Conolly, who moved from space to space engaging in the social rituals that connected the elites within the wider social and political arenas. This study contextualises Conolly’ s activities and the lifestyles of other powerful landowners in Irish society in the mid-nineteenth century. At the core of this study is Castletown, the most important Palladian house in Ireland. Looking at Conolly, a connection to the wider ascendancy society, places Castletown within a world that, in the twenty-first century, has disappeared.