The province of Connacht has the greatest number of native Irish speakers at between 5–10% (40,000–55,000) of the population. There are several important Irish-speaking areas in Counties Galway and Mayo.
Following the Norman invasion of Ireland, the ancient kingdoms were shired into a number of counties for administrative and judicial purposes. In later centuries, local government legislation has seen further sub-division of the historic counties. The province of Connacht has no official function for local government purposes, but it is an officially recognised subdivision of the Irish state. It is listed on ISO-3166-2 as one of the four provinces of Ireland and "IE-C" is attributed to Connacht as its country sub-division code. Along with counties from other provinces, Connacht lies in the North-West constituency for elections to the European Parliament.