The French Revolutionary and Napoleonic wars (1792-1815) resulted in the first truly mass mobilisation of European manpower. The campaigns fought by the British Army during the period 1808-15 were among the most strategically important of the wars for Great Britain and resulted in the expansion of the regular army to a peak of 230,469 men by 1813.1 This placed a significant strain on the British state’s manpower resources and resulted in the large-scale recruitment of Irish men into the regular army, directly impacting many communities across Ireland. While research has been conducted into the mobilisation of British society to meet the demands of ‘total’ war, research within an Irish context has been limited.2 Irish military service during this period has been viewed primarily through the perspective of the Irish militia and yeomanry, with service in the regular army generally considered within the context of the ‘Irish’ regiments of the British Army. This narrow focus has resulted in an under-appreciation of the extent of Irish manpower mobilised by the British state for the defeat of Napoleonic France. Furthermore, it has marginalised or omitted important participants in the historical narrative of the Irish military experience, namely Irish women and children. And finally, it has unintentionally restricted research into the wider impacts on the political, economic, and social relationship between Ireland and Great Britain. This research will address these gaps in the historiography of Irish military service by examining Irish experiences across all regiments of the regular army between 1808 and 1815. The research methodology employed differs significantly from those of other studies of Irish military service during this period as it is based on the quantifiable analysis of data from the military records. Two databases were constructed using biographical details from military service records of enlisted men and officers. A database of 1,913 Irish enlisted men from 45 cavalry and infantry regiments provides unique insights into these men’s social backgrounds and their experiences in the regular army. A second database of 9,378 regular army officers facilitates comparative analysis of the experiences of Irish officers against their English and Scottish colleagues. A third database of 217 regiments and battalions allows for the analysis, by regiment and rank, of the country of birth of 141,527 English, Scottish and Irish enlisted men who served in the regular army. Quantifiable analysis is also conducted on the military records relating to the experiences of thousands of Irish women and children in all regiments of the British Army during the period. This is a new departure for the historiography of early nineteenth century Irish society by placing Irish military experiences during the Napoleonic wars within the broader Anglo/Irish political, social and economic narrative of the period. Analysis of the databases demonstrates that Irish manpower was critical to enabling the British state to prosecute the war in a sustained manner in terms of the numbers of officers and enlisted men serving across all regiments of the regular army. Arising from the scale of Irish recruitment, military service in the regular army impacted Irish society in more ways than previously understood. Men from every parish, town and city in Ireland enlisted in the regular army. Irish women and children accompanied their menfolk and were a significant presence across all regiments of the regular army. This research also addresses important aspects of Irish military service such as religion, welfare, education, discipline and the relationship with military authority, promotion, and transnational experiences. Addressing the topic of Irish military service in a more comprehensive manner utilising empirical based analysis is the focus of this research. It is intended that this will facilitate new perspectives of the relationship between the British Army and the British state with Irish society during this period and in the following decades.