County Donegal is an administrative county in the Republic of Ireland and one of the thirty-two traditional counties of the island of Ireland, located in the province of Ulster. It is the northernmost county in Ireland and is named after the town of Donegal. The population of the county is 147,264 according to the 2006 census. In terms of size and area, it is the largest county in Ulster and the fourth largest county in all of Ireland.At various times in its history, it has been known as County Tirconaill, County Tirconnell or County Tyrconnell. The former was used as its official name during 1922–1927. This is in reference to both the old túath of Tír Chonaill and the earldom that succeeded it.

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