Show ContentsO'Cahil History, Family Crest & Coats of Arms

The original Gaelic form of O'Cahil was Mac Cathail or Ó Cathail, while is derived from the personal name Cathal, which is generally Anglicized as Charles. O'Cahil is derived from the Old Irish "catu-ualos" which means "valor or powerful in battle". 1

Early Origins of the O'Cahil family

The surname O'Cahil was first found in County Kerry and Tipperary as there are at least two distinct septs of the name. The first sept from County Kerry descend from the Heremon line of kings and were known as the Cahills of Connaught. The second sept claim descent from the Ir line of kings and were located at Corkashinny, or the parish of Templemore, Tipperary. This line further branched to the eponymous Ballycahill, Tipperary. Both branches descended from O'Connors, the Kings of Connacht, specifically "Cathal," also known as Conor na Luinge Luaithe, when anglicized means "Conor, the Swifter-Sailing Ship" 2 which may elude to the seafaring coat of arms used by the family.

Early History of the O'Cahil family

This web page shows only a small excerpt of our O'Cahil research. Another 138 words (10 lines of text) covering the years 1654, 1796 and 1864 are included under the topic Early O'Cahil History in all our PDF Extended History products and printed products wherever possible.

O'Cahil Spelling Variations

During the Middle Ages, a standardized literary language known by the general population of Ireland was a thing of fiction. When a person's name was recorded by one of the few literate scribes, it was up that particular scribe to decide how to spell an individual's name. So a person could have several spelling variations of his name recorded during a single lifetime. Research into the name O'Cahil revealed many variations, including Cahill, O'Cahill, Kahill, Cawhill, Cahille, Cahil, Cahaly, Cahell, Cahel, Caughell, Kahil, Kahel, Caill, Cail and many more.

Early Notables of the O'Cahil family

Notable among the family name at this time was

  • Flan O'Cahill, martyred in 938
  • Daniel O'Cahill, brother of Bogh O'Cahill, chief of the Clan, forfeited under the Cromwellian settlement, his castle and the lands of Ballycahill having to move to Ballyglass, County Mayo in 1654

Migration of the O'Cahil family

The 18th century saw the slow yet steady emigration of Irish families to British North America and the United States. Those early Irish settlers that left their homeland were typically moderately well off: they were enticed by the promise of a sizable plot of land. However, by the 1840s, this pattern of immigration was gone: immigrants to North America were seeking refuge from the starvation and disease that the Great Potato Famine of that decade brought. The great numbers of Irish that arrived to the United States and the soon to be Canada were instrumental in their quick development as powerful industrial nations. An examination of early immigration and passenger lists uncovered many early immigrants bearing the name O'Cahil: Elizabeth Cahill, a bonded passenger, who arrived in America in 1735; Thomas Cahill, an "enforced emigrant" sent to America from Ireland in 1737.



The O'Cahil Motto +

The motto was originally a war cry or slogan. Mottoes first began to be shown with arms in the 14th and 15th centuries, but were not in general use until the 17th century. Thus the oldest coats of arms generally do not include a motto. Mottoes seldom form part of the grant of arms: Under most heraldic authorities, a motto is an optional component of the coat of arms, and can be added to or changed at will; many families have chosen not to display a motto.

Motto: In Domino confido
Motto Translation: I trust in the Lord.


  1. MacLysaght, Edward, The Surnames of Ireland. Ireland: Irish Academic Press, sixth edition, 1985. Print. (ISBN 0-7165-2366-3)
  2. O'Hart, John, Irish Pedigrees 5th Edition in 2 Volumes. Baltimore: Genealogical Publishing Company, 1976. Print. (ISBN 0-8063-0737-4)


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