Irish province

Ireland has historically been divided into four provinces: Connacht , Leinster (Laighin), Munster (An Mhumhain) and Ulster (Uladh). The Irish word for this territorial division, cúige, literally meaning "fifth part", indicates that there were once five; the fifth province, Meath (An Mhí), was incorporated into Leinster and Ulster. The provinces of Ireland serve no administrative or political purposes, but function as historical and cultural entities.

In modern Irish the word for province is cúige (pl. cúigeadh). The modern Irish term derives from the Old Irish cóiced (pl. cóiceda) which literally meant "a fifth". This term appears in 8th century law texts such as Miadslechta and in the legendary tales of the Ulster Cycle where it refers to the five kingdoms of the "Pentarchy". In the 12th-century Lebor na Cert (Book of Rights), the term means province, seemingly having lost its fractional meaning with seven cúigeadh listed. Similarly this seems to be the case in regards to titles with the Annals of Ulster using the term rex in Chóicid (king of the fifth/province) for certain overkings.

The origins of the provinces of Ireland can be traced to the medieval cóiceda (literally "fifths") or "over-kingdoms" of Ireland. There were theoretically five such over-kingdoms, however in reality during the historical period there were always more. At the start of the 9th-century the following are listed: Airgíalla, Connachta, Laigin, Northern Uí Néill (Ailech), Southern Uí Néill (Mide), Mumu, and Ulaid. These seven over-kingdoms are again listed in the 12th-century Lebor na Cert.

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