Irish history

Prehistoric Ireland spans a period from the first known evidence of human presence dated to about 10,500 BC until the emergence of "protohistoric" Gaelic Ireland at the time of Christianization in the 5th century. Christianity subsumed or replaced the earlier polytheism and other forms of Celtic paganism by the end of the 7th century.

The Norman invasion of the late 12th century marked the beginning of more than 800 years of direct English rule and, later, British involvement in Ireland. In 1177 Prince John Lackland was made Lord of Ireland by his father Henry II of England at the Council of Oxford. The Crown did not attempt to assert full control of the island until the rebellion of the Earl of Kildare threatened English hegemony. Henry VIII proclaimed himself King of Ireland and also tried to introduce the English Reformation, which failed in Ireland. Attempts to either conquer or assimilate the Irish lordships into the Kingdom of Ireland provided the initial impetus for a series of Irish military campaigns between 1534 and 1603. This period was marked by a Crown policy of plantation, involving the arrival of thousands of English and Scottish Protestant settlers, and the consequent displacement of the pre-plantation Catholic landholders. As the military and political defeat of Gaelic Ireland became more pronounced in the early seventeenth century, sectarian conflict became a recurrent theme in Irish history.

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