During the First World War thousands of women in Ireland performed a parallel war service to that of men in the British Army. The women joined the Red Cross, St John Ambulance Association, the Irish War Hospital Supply Depot and many other voluntary organisations, offering their time and labour for free. They did so for a variety of motives: personal, political and associational. Many felt a strong identification with the British war effort and a desire to prove their loyalty to Britain, when it was coming under question from Ulster unionists and many of those in Britain, particularly after the Easter Rising. Much of this war service took place through parish organisations connected to the various Protestant denominations or through the pre-existing Anglican women’s organisations: the Mothers’ Union, Girls’ Friendly Society and Young Women’s Christian Association. Although many catholic and nationalist (and catholic nationalist) women supported the war effort, the membership of organisations like the Red Cross was dominated by Protestants. The imbalance in participation levels became even more pronounced after the Easter Rising when war service became even more associated with a British or imperial identity. The relationships between Catholics and Protestants, and between unionist Ulster and southern Ireland became increasingly strained during the war, with women’s war service acting as both a catalyst and a prism for viewing these divisions. This paper uses the war service of women in southern Ireland as a means of exploring southern loyalist identity during this tumultuous period. Dr Fionnuala Walsh is an Irish Research Council postdoctoral research fellow in the Department of History at Trinity College Dublin. She completed her PhD in 2015 and held the 2015-2016 Research Studentship in the National Library of Ireland. She is currently writing a monograph on the impact of the First World War on women in Ireland. Dr Walsh is the membership secretary of the Women’s History Association of Ireland.