Ireland's classical music culture was, for long, strikingly underdeveloped, with a paucity, until recently, both of composers of international reputation and of writing (critical or historical) worthy of international attention. Where the historiography of the topic is concerned, activity was minimal until recent times. After some initial efforts to present basic information about musical activity over the centuries, the need to explain and conceptualise the condition of classical music in Ireland grew. Two writers, Joseph Ryan and Harry White, were to the fore in proposing a theory that has dominated the field since the publication of White's The Keeper's Recital (1998). This theory affirms that the rise of nineteenth-century Irish nationalism, both cultural and political, polarised classical music between narrow political demands (music as reinforcement or symbol of the cause) and a cosmopolitan European culture which in Ireland was damaged by its introduction by, and association with, Ascendancy and British power. The thesis focuses on 1820-1920 as it contests this theory. My research first demonstrates how little concrete historical evidence there is for the theory. Second, it deploys and itself adapts T.C.W. Blanning’s properly historicised adaptation of Jürgen Habermas’s concept of the public sphere. This becomes a tool for escaping nationalist/cosmopolitan polarities and for exploring the dynamics of Irish middle-class urban culture, and the place of classical music within it, in its relation to society at large. This process leads to innovative readings of important figures in music history, to a new conceptualisation of the increasing divergence between British and Irish musical life, to the opening up of rich comparative perspectives and to the reasons behind the failure of classical music to benefit substantially from the cultural mobilisation seen during the Irish Revival and to play a significant role in projecting national identity.