Ulster is the most northerly of the four historic provinces. It consists of counties Antrim, Armagh, Cavan, Derry, Donegal, Down, Fermanagh, Monaghan and Tyrone. Although the name is now often used as shorthand for Northern Ireland, three of its counties, Cavan, Donegal and Monaghan, are part of the Republic of Ireland.
In the earliest known division, the province covered a slightly
different territory, excluding much of what is now Cavan and
coming as far south as Louth. The capital was situated at Emhain
Mhacha, outside Armagh. Attacks from its southern neighbour
Mide (Meath) in the fourth century AD broke it up into smaller
kingdoms: Tír Chonaill covering most of Donegal; Tír Eoghain
covering most of modern Tyrone and Derry; Oriel which included
Monaghan, Louth and Armagh; and Uladh which, although claiming
the name of the province as a whole, in fact only incorporated
the north-eastern counties.
The Normans managed to settle along the east coast from the
twelfth century, but the power of the O'Neills and O'Donnells
remained intact elsewhere in the province until the seventeenth
century when the final collapse of the old Gaelic civilisation
led to the Plantation of Ulster and a massive influx of settlers
from Scotland and England.
The first great mass migration from Ireland to North America
took place from Ulster in the eighteenth century and consisted
of the descendants of the Scottish settlers seeking refuge from
economic and political hardship and religious intolerance.