From around 800 onwards Ireland was attacked by bands of Viking marauders. The
raids continued right through the 9th century and a second major wave began
early in the 10th century.
The monasteries, as the major centres of population and wealth, were the main
target of the Vikings. They were despoiled of their books and valuables and
many of them were burned. These attacks, and attacks by the Irish themselves,
contributed to the decline of the great monastic tradition.
The lack of any political unity made it difficult to resist the Viking attacks.
However, the strength of the U� N�ill kings in the northern half of the country
prevented the Vikings from establishing themselves there.
The Vikings were great traders and did much to develop commerce in medieval
Ireland. They founded most of the major towns such as Dublin, Cork, Limerick
Towards the end of the 10th century a new dynasty emerged in Munster in the
south and, under the kingship of
, was able to match the U� N�ill. Brian Boru defeated the Vikings in 999 and in
1002 he won recognition as king of all Ireland. The Vikings intervened
regularly in the disputes between the Irish kings. Their support for a Leinster
revolt against Brian Boru led to their defeat at the Battle of Clontarf in
1014, after which they were confined to a subsidiary role in Irish political
The 11th and 12th centuries were an age of renaissance and progress in Ireland.
Cultural activity and the arts prospered. It was a great era of religious
reform and a powerful effort was made to bring the church more fully into line
with Roman orthodoxy. Two of the principal figures of this movement were St
Malachy of Armagh (d. 1148) and St Laurence O'Toole of Dublin (d. 1180).
In politics, others sought to follow Brian Boru's example and establish
themselves as kings of all Ireland. At various times between 1014 and 1169 the
kings of Munster, Ulster, Connacht and Leinster succeeded in doing so. The
general trend was towards the development of a strong centralised monarchy on
the European model. This trend was interrupted by the arrival of the Normans in
1167-69. The first Normans came to Ireland from south Wales at the invitation
of Diarmait Mac Murchada, king of Leinster, to support his ambition to become
king of all Ireland. Mac Murchada was succeeded as King of Leinster by the
leader of the Normans, Richard de Clare, known as Strongbow.
In 1171 the Norman overlord, Henry II, King of England, came to Ireland and was
recognised as overlord of the country by both Irish and Normans. Thus began the
political involvement of England in Ireland which was to dominate the country's
history in succeeding centuries. The Normans quickly came to control
three-quarters of the land. In time, they assimilated with the local population
until they became, it was said, more Irish than the Irish themselves.
The Normans had a major impact on the country. Throughout the 13th century they
developed the same type of parliament, law and system of administration as in
England. However, the native, or Gaelic, Irish exerted pressure on the Norman
colony. Outside the colony attempts were made to re-establish the native
kingship. Edward Bruce, brother of the Scottish king Robert, failed in his
attempt in 1315, the last serious effort to overthrow Norman rule.
By the end of the 15th century, due to the depredations of the Irish and the
Gaelicisation of the leading Norman families, the area of English rule in
Ireland had shrunk to a small enclave around Dublin known as the Pale.