McKinley (surname) McKinley (surname) McKinley is a Scottish and Irish surname historically associated with northwestern Ireland's County Donegal, and the over-kingdom of Ulaid in northeastern Ireland and the Scottish Highlands. The McKinley are of the ancient Ulaid race and are a branch of its "Red Branch" MacDunleavy (dynasty) royal house of the Dal Fiatach which dominated the kingship of the over-kingdom of Ulaid (original Gaelic language Mac Duinnshléibhe). Etymology for the origins of the surname proposes that the Anglicized surname McKinley, like the surname MacNulty (Gaelic Mac an Ultaigh, trans. "son of the ultonian, ulidian or ulsterman"), arose originally from a Gaelic
Surname as well as "FitzWilliam" or "Fitzwilliam". Irish surnames are the oldest surnames in Europe. The common prefixes "Ó" and "Mac" can be spelled with the prefix as a separate word, yielding "Ó Briain" or "Mac Millan" as well as the anglicized "O'Brien" and "MacMillan" or "Macmillan". In the United States, 1,712 surnames cover 50% of the population, and about 1% of the population has the surname Smith, which is also the most frequent English name and an occupational name ("metal worker"), a contraction, for instance, of blacksmith or other metalsmiths. Several American surnames are a result of corruptions or phonetic