Mulligan comes from the Irish O Maolagain, from a diminutive of maol, literally meaning "bald" and referring to the distinctive tonsure of the early Irish monks. In the early middle ages, they were rulers of the territory of Tir MacCarthain, in the baronies of Boylagh and Raphoe in Co. Donegal, and held power down to the plantation of the seventeenth century. After this they were dispersed, and migrated south to Mayo and east to counties Fermanagh and Monaghan. Some members of the family anglicised their surname, by quasi-translation, to Baldwin. Milligan is another common variant, found most frequently in counties Antrim, Down and Derry. Hercules Mulligan (1740-1825), born in Coleraine, acted as a secret agent for George Washington, during the War of Independence.