Show ContentsGeo History, Family Crest & Coats of Arms

The original Gaelic form of the Geo surname is Mag Eochagain, a patronymic derived from the personal name Eochaidh.

Early Origins of the Geo family

The surname Geo was first found in the county of Westmeath (Irish: An Iarmhí) in the Irish Midlands, province of Leinster, in the barony of Moycashel at Kilbeggan where they held a family seat from ancient times. Traditionally, the Geos are said to descend from Fiacha, son of Niall of the Nine Hostages.

Early History of the Geo family

This web page shows only a small excerpt of our Geo research. Another 148 words (11 lines of text) covering the years 1172, 1186, 1291, 1580, 1600, 1603, 1650, 1689, 1702, 1749, 1763 and 1800 are included under the topic Early Geo History in all our PDF Extended History products and printed products wherever possible.

Geo Spelling Variations

Numerous spelling variations of the surname Geo exist. A partial explanation for these variants is that ancient scribes and church officials recorded names as they were pronounced, often resulting in a single person being recorded under several different spellings. Different spellings that were found include Geoghegan, Gagahan, Gahagan, Gahaghan, Gaghan, Gegan, MacGeoghegan, Geohan and many more.

Early Notables of the Geo family

Prominent amongst the family at this time was

  • Conal MacGeoghegan (circa 1580-1650) Chief of the sept MacGeoghegan, historian who translated the Annals of Clonmacnoise; James MacGeoghegan (1702-1763) of Westmeath, an ordained priest in Paris, who...


United States Geo migration to the United States +

Many destitute Irish families in the 18th and 19th centuries decided to leave their homeland, which had in many ways been scarred by English colonial rule. One of the most frequent destinations for these families was North America where it was possible for an Irish family to own their own parcel of land. Many of the early settlers did find land awaiting them in British North America, or even later in America, but for the majority of immigrants that arrived as a result of the Great Potato Famine of the late 1840s the ownership of land was often a long way off. These Irish people were initially put to work on such industrial projects as the building of bridges, canals, and railroads, or they worked at manufacturing positions within factories. Whenever they arrived, the Irish made enormous contributions to the infant nations of Canada and the United States. Some of the earliest immigrants to bearer the name of Geo were found through extensive research of immigration and passenger lists:

Geo Settlers in United States in the 17th Century
  • David Geo, who arrived in Virginia in 1664 1

Contemporary Notables of the name Geo (post 1700) +

  • Geo Joseph Fertig (b. 1899), chemical engineer


  1. 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)


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