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Irish surname

McMahon: Irish Surname History & Coat of Arms

Mac Mathghamhna · 'son of Mathghamhain' (bear)

McMahon is an anglicised form of the Irish surname Mac Mathghamhna, 'son of Mathghamhain' (bear). Woulfe (1923) describes two great families of the name: the MacMahons of Thomond in Co. Clare, a branch of the O'Briens, and the MacMahons of Oriel, who were powerful in Co. Monaghan. Bearers include Heber MacMahon, Bishop of Clogher, and Marshal MacMahon, President of the French Republic.

Coat of arms associated with the McMahon surname
Irish formMac Mathghamhna
Meaning'son of Mathghamhain' (bear)
CountiesClare, Monaghan, Limerick, Dublin
Other spellings4

Origin of the McMahon name

Woulfe gives two families. The MacMahons of Thomond descend from Mahon, son of Murtagh More O'Brien, King of Ireland, and held Corca Bhaiscinn in south-west Clare. The MacMahons of Oriel became lords of Oriel after the decline of the O'Carrolls in the 13th century.[1]

  1. 1094–1119Reign of Murtagh More O'Brien, whose son Mahon gave the Thomond family its name.[1]
  2. 1602Last Thomond chief accidentally killed by his own son at Bearhaven.[1]
  3. 1641Hugh MacMahon, last chief of Oriel, arrested over the plot to seize Dublin Castle.[1]
  4. 1644Hugh MacMahon beheaded at Tyburn.[1]
  5. 1650Bishop Heber MacMahon defeated at Scarriffhollis, captured and hanged.[3]
  6. 1859Patrice de MacMahon created marshal and Duc de Magenta after Magenta.[4]
  7. 1873National Assembly elects MacMahon President of the French Republic.[4]

Where in Ireland

Co. ClareThe MacMahons of Thomond held Corca Bhaiscinn (baronies of Moyarta and Clonderlaw). First county listed in 1890.[1][2]
Co. MonaghanThe MacMahons of Oriel kept considerable possessions and power there as late as the Cromwellian wars.[1]
Co. LimerickOne of the counties where the name was principally found in the 1890 birth indexes.[2]
Co. DublinOne of the counties where the name was principally found in the 1890 birth indexes.[2]

Notable people named McMahon

Hugh MacMahond. 1644Last chief of the MacMahons of Oriel; arrested in 1641, sent to the Tower of London, beheaded at Tyburn.[1]
Heber MacMahond. 1650Bishop of Clogher from 1643 and commander of the Ulster Irish after Owen Roe O'Neill's death.[3]
Patrice de MacMahon, Duc de Magenta1808–1893Marshal of France and President of the French Republic; the Catholic Encyclopedia says his ancestors were Irish.[4][1]

Other spellings

MacMahon · MacMahan · MacMann · Mahon[1]

The McMahon coat of arms

The design shown is a coat of arms associated with the McMahon surname. In Irish and British heraldry a coat of arms is granted to one person and passes to their heirs; it does not belong to everyone who shares the surname. Many families still use the arms of their name as a symbol of their heritage.

McMahon crest gifts

McMahon surname: questions

What does the surname McMahon mean?

Woulfe gives McMahon as an anglicised form of Mac Mathghamhna, 'son of Mathghamhain', a personal name he glosses as 'bear'.[1]

Where in Ireland is the McMahon name from?

Woulfe records two great families: the MacMahons of Thomond in south-west Co. Clare (Corca Bhaiscinn) and the MacMahons of Oriel, powerful in Co. Monaghan. In the 1890 birth indexes the name was principally found in Clare, Monaghan, Limerick and Dublin.[1][2]

Are the McMahons related to the O'Briens?

Woulfe says the MacMahons of Thomond are a branch of the O'Briens, descended from Mahon, son of Murtagh More O'Brien, King of Ireland (1094–1119). He gives no O'Brien link for the MacMahons of Oriel.[1]

Was Marshal MacMahon Irish?

He was born in France in 1808. The Catholic Encyclopedia says his ancestors were Irish and had been settled in France since the time of James II; Woulfe places him in the MacMahon of Thomond family.[4][1]

Sources

  1. Mac Mathghamhna — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/macm/mac-mathghamhna.php
  2. McMahon — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), birth indexes of 1890, transcribed, LibraryIreland.com. libraryireland.com/matheson/report/births/mcmahon.php
  3. Heber MacMahon, Bishop of Clogher — A Compendium of Irish Biography (Alfred Webb, 1878), transcribed, LibraryIreland.com. libraryireland.com/biography/BishopHeberMacMahon.php
  4. Marie-Edmé-Patrice-Maurice de MacMahon — Catholic Encyclopedia (1907–1912), New Advent. newadvent.org/cathen/09504c.htm

Note: Matheson's 1890 figures for a surname include its spelling varieties (Matheson, Table Explanation).