Show ContentsCasidy History, Family Crest & Coats of Arms

Irish names tend to vary widely in their spelling and overall form. The original Gaelic form of the name Casidy is O Casaide. IF)

Early Origins of the Casidy family

The surname Casidy was first found in Fermanagh (Irish: Fear Manach) in the southwestern part of Northern Ireland, Province of Ulster, where the Irish sept claims direct descent from the Irish King Colla da Crioch who was banished from Ireland in 327. [1]

Early History of the Casidy family

This web page shows only a small excerpt of our Casidy research. Another 96 words (7 lines of text) covering the years 1143 and 1740 are included under the topic Early Casidy History in all our PDF Extended History products and printed products wherever possible.

Casidy Spelling Variations

The Middle Ages saw a great number of spelling variations for surnames common to the Irish landscape. One reason for these variations is the fact that surnames were not rigidly fixed by this period because the general population had to rely on local official's understanding of how their name should be spelt, hence spellings in records often changed through a person's lifetime. The following variations for the name Casidy were encountered in the archives: Cassidy, Cassady, Cassiday, Cassedy, Cassedey and others.

Early Notables of the Casidy family

More information is included under the topic Early Casidy Notables in all our PDF Extended History products and printed products wherever possible.


United States Casidy migration to the United States +

Ireland became inhospitable for many native Irish families in the 19th centuries. Poverty, lack of opportunities, high rents, and discrimination forced thousands to leave the island for North America. The largest exodus of Irish settlers occurred with the Great Potato Famine of the late 1840s. For these immigrants the journey to British North America and the United States was long and dangerous and many did not live to see the shores of those new lands. Those who did make it were essential to the development of what would become two of the wealthiest and most powerful nations of the world. These Irish immigrants were not only important for peopling the new settlements and cities, they also provided the manpower needed for the many industrial and agricultural projects so essential to these growing nations. Immigration and passenger lists have documented the arrival of various people bearing the name Casidy to North America:

Casidy Settlers in United States in the 18th Century
  • Corook Casidy, who arrived in Virginia in 1705 [2]


The Casidy 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: Frangas non flectes
Motto Translation: Thou may'st break, but shalt not bend me.


  1. O'Hart, John, Irish Pedigrees 5th Edition in 2 Volumes. Baltimore: Genealogical Publishing Company, 1976. Print. (ISBN 0-8063-0737-4)
  2. 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)


Houseofnames.com on Facebook