Show ContentsCalahan History, Family Crest & Coats of Arms

Before Irish names were translated into English, Calahan had a Gaelic form of Ó Ceallachain, possibly from "ceallach", which means "strife". The family is descended from Ceallachan (Callaghan), the 10th century King of Munster from whom their surname is derived, and as such, the name Calahan is a patronymic name. 1

Early Origins of the Calahan family

The surname Calahan was first found in Munster. The earliest mention of the name Calahan placed them in the barony of Kinlea, in County Cork, yet the family lost most of their original lands in the barony of Kinelea during the Anglo-Norman Conquest under Strongbow. They relocated to an area near Mallow, in the north of the county, and remained there until forced off their lands once again during the Cromwellian Invasion of the 17th century.

The head family migrated to the east of County Clare and flourished, giving their name to the village of Callaghan's Mills. The resumption of the often-discarded prefix "O" has been widespread during the late twentieth century, but in the early twentieth century, Callaghans greatly outnumbered O'Callaghans, but such is no longer the case. The O'Callaghans are one of the few Irish families to still have a chief, certified by the Genealogical Office. 2

Early History of the Calahan family

This web page shows only a small excerpt of our Calahan research. Another 202 words (14 lines of text) covering the years 1172, 1605, 1640, 1654, 1738, 1797, 1807, 1839, 1883 and 1909 are included under the topic Early Calahan History in all our PDF Extended History products and printed products wherever possible.

Calahan Spelling Variations

The scribes who created documents long before either the Gaelic or English language resembled their standardized versions of today recorded words as they sounded. Consequently, in the Middle Ages the names of many people were recorded under different spellings each time they were written down. Research on the Calahan family name revealed numerous spelling variations, including Callaghan, Callahan, O'Callaghan, O'Callahan, Calahan, Cellaghan, Kalahan, Kallaghan, Kallahan, O'Kallaghan, Kellaghan, Kelleghan, Kellahan, Kelahan, Ceilahan, Ceilaghan, Callachan, Calachan, Callagan, Calagan, Kelagan, Callighan and many more.

Early Notables of the Calahan family

Another 35 words (2 lines of text) are included under the topic Early Calahan Notables in all our PDF Extended History products and printed products wherever possible.

Calahan Ranking

In the United States, the name Calahan is the 10,254th most popular surname with an estimated 2,487 people with that name. 3


United States Calahan migration to the United States +

Many Irish families boarded ships bound for North America in the middle of 19th century to escape the conditions of poverty and racial discrimination . Although these immigrants often arrived in a destitute state, they went on to make important contributions to the emerging nations of the United States and Canada. An inquiry into many immigration and passenger lists has revealed many early immigrants to North America bearing the Calahan family name:

Calahan Settlers in United States in the 19th Century
  • James Calahan, aged 35, who landed in Maryland in 1813 4
  • John Calahan, aged 25, who arrived in Pennsylvania in 1814 4
  • Philip Calahan, who arrived in Mobile County, Ala in 1845 4
  • Patrick Calahan, who landed in Allegany (Allegheny) County, Pennsylvania in 1848 4
  • Michael Calahan, who landed in Allegany (Allegheny) County, Pennsylvania in 1871 4

Canada Calahan migration to Canada +

Some of the first settlers of this family name were:

Calahan Settlers in Canada in the 18th Century
  • Bartholomew Calahan, who arrived in Nova Scotia in 1749-1752
  • Hart Calahan, who landed in Halifax, Nova Scotia in 1752

Australia Calahan migration to Australia +

Emigration to Australia followed the First Fleets of convicts, tradespeople and early settlers. Early immigrants include:

Calahan Settlers in Australia in the 19th Century
  • Michael Calahan, who arrived in South Australia in 1855 aboard the ship "David Malcolm" 5
  • Nicholas Calahan, aged 25, who arrived in South Australia in 1855 aboard the ship "David Malcolm" 5
  • Mary Calahan, aged 20, a servant, who arrived in South Australia in 1855 aboard the ship "Glentanner" 6


  1. MacLysaght, Edward, The Surnames of Ireland. Ireland: Irish Academic Press, sixth edition, 1985. Print. (ISBN 0-7165-2366-3)
  2. MacLysaght, Edward, Irish Families Their Names, Arms and Origins 4th Edition. Dublin: Irish Academic, 1982. Print. (ISBN 0-7165-2364-7)
  3. "What are the 5,000 Most Common Last Names in the U.S.?". NameCensus.com, https://namecensus.com/last-names/
  4. Filby, P. William, Meyer, Mary K., Passenger and immigration lists index : a guide to published arrival records of about 500,000 passengers who came to the United States and Canada in the seventeenth, eighteenth, and nineteenth centuries. 1982-1985 Cumulated Supplements in Four Volumes Detroit, Mich. : Gale Research Co., 1985, Print (ISBN 0-8103-1795-8)
  5. South Australian Register Tuesday 1st May 1855. (Retrieved 2010, November 5) David Malcolm 1855. Retrieved http://www.theshipslist.com/ships/australia/davidmalcolm1855.shtml
  6. South Australia Passengerlists (Retrieved 10th November 2010). Retrieved from https://archives.sa.gov.au/sites/default/files/documentstore/passengerlists/1855/GRG35_48_1_55-35_Glentanner.pdf


Houseofnames.com on Facebook