Ireland in World War I

During World War I (1914–1918), Ireland was part of the United Kingdom of Great Britain and Ireland, which entered the war in August 1914 as one of the Entente Powers, along with France and the Russian Empire. In part as an effect of chain ganging, the UK decided due to geopolitical power issues to declare war on the Central Powers, consisting of the German Empire, the Austrian-Hungarian Empire, the Ottoman Empire, and the Kingdom of Bulgaria.

Occurring during Ireland's Revolutionary period, the Irish people's experience of the war was complex and its memory of it divisive. At the outbreak of the war, most Irish people, regardless of political affiliation, supported the war in much the same way as their British counterparts, and both nationalist and unionist leaders initially backed the British war effort. Their followers, both Catholic and Protestant, served extensively in the British forces, many in three specially raised divisions with others in the Imperial and United States armies, John T. Prout being an example of an Irishman serving in the latter. Over 200,000 Irishmen fought in the war, in several theatres and either 30,000, or, if one includes those who died serving in armies other than Britain's, 49,400 died.

In 1916, supporters of Irish independence from Great Britain took the opportunity of the ongoing war to proclaim an Irish Republic and to defend it in an armed rebellion against British rule in Dublin, a rebellion which Germany attempted to help. In addition, Britain's intention to impose conscription in Ireland in 1918 provoked widespread resistance and as a result remained unimplemented.

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