Hayes is a common surname in England, where it derives from various places of the same name and from the Norman De la Haye, but in Ireland it is almost always the most common anglicisation of the Irish O hAodha, from the personal name Aodh, "fire", which was very popular in early Ireland. No doubt this popularity accounts for the fact that the surname originated separately in at least twelve different locations, including south-west Cork, Limerick/Tipperary, south Donegal, Sligo, Monaghan, Meath, Mayo, north Tyrone, south Down, Armagh, and Wexford. As well as Hayes, the surname was also anglicised as "O'Hea", particularly in south-west Cork, and as "Hughes", since Aodh was invariably translated as "Hugh". This last anglicisation is most common among the five septs originating in the Ulster counties.
Hughes is common in England and Wales, where it is a patronymic, deriving from the father's name, and quite a few Irish bearing the name, particularly in Ulster, will be of English and Welsh stock. Elsewhere, it is almost always one of the anglicisations of the Irish O hAodha, from the personal name Aodh, "fire", the second most popular such anglicisation after "Hayes", since Aodh was invariably translated as "Hugh". Perhaps because of the example of the settlers, Hughes was the most frequent anglicisation amongst the Gaelic Irish in Ulster, where there were O hAodha at Ballyshannon (Co. Donegal), Ardstraw (Co. Tyrone), Tynan (Co. Armagh), Farney (Co. MOnaghan), and south Co. Down. In places, too, Hughes became the English version of Mac Aoidh or Mac Aodha, more usually given as Magee or McHugh/McCue.