Early Medieval Ireland

The history of Ireland 800–1169 covers the period in the history of Ireland from the first Viking raids to the Norman invasion. The first two centuries of this period are characterised by Viking raids and the subsequent Norse settlements along the coast. Viking ports were established at Dublin, Wexford, Waterford, Cork and Limerick, which became the first large towns in Ireland.

Ireland consisted of many semi-independent túatha, and during the entire period, attempts were made by various factions to gain political control over the whole of the island. For the first two centuries of this period, this was mainly a rivalry between putative High Kings of Ireland from the northern and southern branches of the Uí Néill. The one who came closest to being de facto king over the whole of Ireland, however, was Brian Boru, the first high king in this period not belonging to the Uí Néill.

Following Brian's death at the Battle of Clontarf in 1014, the political situation became more complex with rivalry for high kingship from several clans and dynasties. Brian's descendants failed to maintain a unified throne, and regional squabbling over territory led indirectly to the invasion of the Normans under Richard de Clare in 1169.

Due to the rich amount of written sources, the study of Irish history 800–1169 has, to a large extent, focused on gathering, interpretation and textual criticism of these. Only recently have other sources of historical knowledge received more attention, particularly archaeology. Since the modern excavations of Dublin started in 1961, followed by similar efforts in Wexford, Waterford and Limerick, great advances have been made in the understanding of the physical character of the towns established during this period.

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