County Monaghan shares border with Northern Ireland
County Monaghan ( MON-ə-hən; Irish: Contae Mhuineacháin) is a county in Ireland. It is in the province of Ulster and is part of Border strategic planning area of the Northern and Western Region. It is named after the town of Monaghan. Monaghan County Council is the local authority for the county. The population of the county was 61,386 according to the 2016 census.The county has existed since 1585 when the Mac Mathghamhna rulers of Airgíalla agreed to join the Kingdom of Ireland. Following the 20th-century Irish War of Independence and the signing of the Anglo-Irish Treaty, Monaghan was one of three Ulster counties to join the Irish Free State rather than Northern Ireland.
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