The Orthodox is the fastest growing religious grouping in Ireland according to the 2011 census, showing a growth rate of 117% since 2006. According to the official record, in 1991 there were just 358 Orthodox in Ireland, by 2011 this had grown to 45,223. This chapter will briefly survey the history of Orthodoxy in 20th century Ireland and chart the course of this dramatic rise in numbers before addressing the question of the role and agency of local “converts” to Orthodoxy both as mediators of the local context and innovators within Irish Orthodoxy. Although the exponential rise in the number of Orthodox Christians is the result of mass labour migration, I argue here that the construction of Orthodox space in Ireland, both physical and conceptual, has been profoundly shaped by the agency of local “converts.” I will explore here two aspects of this relationship, firstly looking at the role played by converts in the founding of congregations and the establishment of Orthodox institutions in Ireland, referring to the cases of the Romanian, Antiochian and Georgian Orthodox Churches. Secondly, I explore the phenomenon of “discursive autochthonism” - and the practices that flow from this - amongst “cradle” and convert Orthodox, a blend of historical revisionism of the Celtic Christian past and “memory and meaning” making in the Irish Landscape. These two arenas of agency, institutionalization and autochthonist practices, are contributing to the emergence of a “fluid” intra-Orthodox space in Ireland.