The Irish Civil War occurred following the signing of a treaty between Sinn Fein and the British government. The Anglo-Irish Agreement brought the Irish War of Independence to an end and established the Irish Free State. The civil war caused a split in the nationalist movement between those who supported the Treaty with Britain and those who were opposed. It created deep divisions that lasted in Irish society for decades. The two main political parties since the foundation of the state, Fine Gael and Fianna Fail, are direct descendants from the pro-Treaty and anti-Treaty sides in the civil war. The civil war began as a result of divisions over the Anglo-Irish Treaty. However, other factors also played a role in these divisions. This essay will look at the role the Anglo-Irish Treaty played in bringing about the civil war and what other differences also caused divisions during this period.
The Anglo-Irish Treaty was agreed between Sinn Fein representatives and the British government in December 1921. The signing of the Treaty led to an bitter debate in the Dail before being accepted by a slim majority in January 1922. The divisions in the Dail spilled over into the wider nationalist movement and into the ranks of the IRA. A number of issues in the Anglo-Irish Treaty caused disagreements the most prominent being the Oath of Allegiance to the British crown and the partition of Ireland into North and South. The Oath of Allegiance was highly objectionable to many republicans and was the most divisive issue in the Treaty. Those opposed could not understand why they should be forced to swear allegiance to a British king that they had fought against only weeks earlier. For those who were seeking an independent republic swearing an oath of allegiance to a foreign king went against everything they believed in. The inclusion of the oath of allegiance was to be a significant contributing factor to the divisions that caused the civil war.