|Author||Rev Patrick Woulfe|
|Source||Irish Names and Surnames|
Mac MATHGHAMHNA—IV—M'Mahowna, M'Maghowney, M'Maghone, M'Machan, MacMaghone, MacMaghon, MacMaghen, MacMachon, MacMahon, MacMahan, MacMann, Mahony, Mahon, (Matthews, Mathews); 'son of Mathghamhain' (bear). There are two great Irish families of this name, viz.: the MacMahons of Thomond, and the MacMahons of Oriel. The MacMahons of Thomond are a branch of the O'Briens, and derive their name and descent from Mahon, son of Murtagh More O'Brien, King of Ireland (1094-1119). Their patrimony was Corca Bhaiscinn, which comprised the baronies of Moyarta and Clonderlaw in the south-west of Co. Clare. The last chief of the name was accidentally killed by his own son at Bearhaven in the year 1602. To this family belonged the celebrated Marshal MacMahon, Duke of Magenta and President of the French Republic. The MacMahons of Oriel were formerly one of the most powerful families in Ulster. On the decline of the O'Carrolls in the 13th century, they became lords of Oriel, a rank which they retained down to the reign of Elizabeth; and even as late as the Cromwellian wars, they had considerable possessions and power in Co. Monaghan. The last chief of the family was Hugh MacMahon who was arrested for complicity in the plot to seize Dublin Castle in 1641, sent to the Tower of London, and, in 1644, beheaded at Tyburn. Besides distinguished chiefs, this family produced many eminent ecclesiastics, three of whom successively filled the primatial see of Armagh in the first half of the 18th century.
Alphabetical Index to Irish Surnames