Leinster is situated in the eastern part of Ireland. It is surrounded by Connacht and Munster to the west, Ulster to the north, the Irish Sea to the east and the Atlantic ocean to the south. It covers an area of 7,618 square miles and has a  population of  1,851,134. Generally, Leinster has fared better economically than the other provinces, primarily because Dublin, the historic center of power and influence in Ireland, is located within its boundaries. It is the most densely populated province with a population density of 242 per square mile, compared to Connacht with a density of 63 per square mile.

Within the Eire Nua concept, Leinster's parliament would be seated in Dublin, the capital. The parliament would consist of a single chamber of deputies elected by the people of the province according to a system of proportional representation. The function of the parliament would be to 1) coordinate cultural activity and economic development within its regions, 2) initiate and promote legislation for the social, economic and cultural development, 3) coordinate the development of third-level education, and 4) collect taxes.

In order to maximize the concept of devolved government, Leinster would include within its geographic boundary four clearly defined regions, namely, the Midlands, South Leinster, East Leinster and Greater Dublin. Each region would be administered by a regional board consisting of 1) representatives of district councils from within the region, and 2) expert representatives appointed by the provincial parliament. These regional boards would be responsible for administering the criminal justice system and for establishing, promoting and coordinating their own social, economic and cultural programs.

Within each region, clearly defined districts would be established. The Midlands would have six, South Leinster would have six , East Leinster would have seven and Greater Dublin would have thirty-two. Each district, which would have a population of between 10,000 and 40,000 people, would be administered by a district council. District councils would be responsible for 1) primary and secondary education, 2) public works and local planning, 3) welfare and social  services and  4) recreational development.