This thesis explores the historical processes of becoming in the everyday social lives of Irish Catholic immigrants in nineteenth-century Christchurch. My central argument is that these newcomers effected a transition to colonial life by creating and sustaining durable social networks based on ethnic ties which transcended pre-existing affiliations and represented a powerful means to appropriate a new environment. In my introduction, I argue that our limited understanding of settler society has legitimated cultural silences which marginalise the pluralistic experiences of immigrants in nineteenth-century immigrants New Zealand. Chapter One examines the process of migration and the interpersonal networks on which the vast majority of Irish Catholics were reliant for assistance both in moving to and settling in the city and its environs. Chapter Two charts the development of ethnic consciousness among the newcomers, while Chapter Three explores the question of transience and attempts to refute the view that itinerancy and a lack of associative bonds conspired to stunt the emergence of ethnic social relations. Paralleling this line of argument, Chapter Four focuses on the social topography of settlement and uses a variety of sources to demonstrate how newcomers expressed their ethnicity spatially within the city through a process of residential bonding. By contrast, Chapter Five deals with the vexing question of social mobility and seeks to establish whether the popular stereotype of the downtrodden Irish is relevant or applicable to those immigrants who settled in Christchurch. Its findings indicate that Irish Catholics were neither culturally emaciated nor crippled by persistent poverty in the city but instead made steady but modest gains within a generation. Chapter Six enlarges the analyzable context of the social ties that bound the immigrants to one another through an examination of evidence adduced from wills. In conclusion, I argue that Irish Catholics mobilized and sustained their ethnicity in the city by creating complex associative networks within which they pursued collective and individual goals. Their social agency, I suggest, resided in a capacity for reflexive self-knowledge, along with an ability to alter the circumstances and conditions of their everyday world.