This is what we found on Wikipedia regarding the Munster:

Munster (Irish: an Mhumhain [ə ˈwuːnʲ] or Cúige Mumhan [ˌkuːɟə ˈmˠuːnˠ]) is one of the four provinces of Ireland, located in the south of the island. In early Ireland, the Kingdom of Munster was one of the kingdoms of Gaelic Ireland ruled by a "king of over-kings" (Irish: rí ruirech). Following the Norman invasion of Ireland, the ancient kingdoms were shired into counties for administrative and judicial purposes. In later centuries, local government legislation has seen further sub-division of the historic counties.

Munster has no official function for local government purposes. For the purposes of the ISO, the province is listed as one of the provincial sub-divisions of the State (ISO 3166-2:IE) and coded as "IE-M". Geographically, Munster covers a total area of 24,675 km² (9,527 sq mi) and has a population of 1,373,346, with the most populated city being Cork. Other significant urban centres in the province include Limerick and Waterford.