was built in the 4th millennium BC County Waterford is colloquially known as "The Déise", pronounced "day-shah" or, in Irish, /dʲe:ʃʲɪ/ (). Some time between the 4th and 8th centuries, an
Irish tribe called the
Déisi were
driven from southern county Meath/north Kildare and moved into the Waterford region, conquering and settling there. The ancient principality of the Déise is today roughly coterminous with the current
Roman Catholic Diocese of Waterford and Lismore thus including part of south
County Tipperary. The westernmost of the baronies are Decies-within-Drum and Decies-without-Drum, separated by the Drum-Fineen hills. , County Waterford There are many
megalithic tombs and
ogham stones in the county. The
Viking influence can still be seen with Reginald's Tower, one of the first buildings to use a brick and mortar construction method in Ireland.
Woodstown, a settlement dating to the 9th century, was discovered west of
Waterford city. It was the largest settlement outside Scandinavia and the only large-scale 9th-century Viking settlement discovered to date in Western Europe. Other architectural features are products of the
Anglo-Norman invasion of Ireland and its effects. ==Local government and politics==