Donlevy is a surname of Irish origin. Also spelt as MacDonlevy, Donleavy, Dunleavy, and MacAleavey, it derives from the Irish Mac Duinnshléibhe, meaning "brown mountain". Ó Duinnshléibhe is a variant Irish spelling. Their eponymous ancestor is Donn Sléibe mac Echdacha, who ruled as king of the Irish petty-kingdom of Dál Fiatach, as well as its over-kingdom, Ulaid, in the late 10th century. In the aftermath of John de Courcy's conquest of Ulaid in 1177, some of the dynasty migrated to present-day County Donegal in the Republic of Ireland, whilst others went to Scotland. In Donegal they became the hereditary physicians (Old Irish: ollahm leighis) of the Cenél Conaill of Tír Conaill. - Source: Wikipedia