Cassidy Surname Meaning, History & Origin

Cassidy Surname Meaning

The Irish surname Cassidy and its variants Cassiday, Casaday, Cassedy, and Casidy are anglicized forms of the Gaelic name O’Caiside, a derivative of cas, meaning “curly headed.”  The name originated in county Fermanagh.   

Cassidy Surname Resources on the Internet    

Cassidy Surname Ancestry

  • from Ireland (Fermanagh)
  • to Scotland, America, Canada and New Zealand

Ireland.  All Cassidys came originally from Fermanagh, where for centuries they were prominent not in warfare but in peace, culture, and scholarship.  Their ancient home was Ballycassidy, just north of Enniskillen.

The bardic poet Giolla Mochuda Mor O’Casside was famed among the men of learning of his time. He wrote the poem Banshenchas (The Lore of Woman) in 1147 which tells of the history of women in the world.

From the 1300’s, when the Maguires assumed control of Fermanagh, the Cassidys acted as their hereditary physicians and were, during that time, the authors of several medical tracts.  They were also one of the church families of Fermanagh.  However, after the Scottish plantations in the early 17th century, the Cassidys, like nearly all the leading Gaelic families in the province, lost their power as chiefs.

There are still Cassidys in Fermanagh.  But many moved away to the nearby counties of Meath, Cavan, and Donegal; and others emigrated.

England and Scotland.  That Cassidys are to be found in Glasgow and Lancashire is not surprising as these were the closest immigrating points for Irishmen seeking a better life.  This description of James Cassidy from Enniskillen may have been typical of many who crossed the Irish Channel:  

“James was an agricultural laborer and would have lived with his family in a cottage made of rough stone with a thatched roof.  There would have been separations for a kitchen and a bedroom which allowed little for home comforts.  The food was chiefly potatoes, fish, pottage, milk, butter, and eggs. As a farm laborer, James was earning no more than 10d per day.”  

James left Fermanagh in 1840 with his wife and three children for Glasgow where they all worked in the cotton mills.  His grandson was able to escape these mills.  James Rice Cassidy set up his own theatrical company with his wife Lilian and toured the north of England, to great acclaim, in the early 1900’s.

Another who made it was John Cassidy from county Meath.  He had moved to Manchester and became a well-known sculptor in the inter-war years through his various public works.

America.  The first arrivals may well have been indentured servants.  Catherine Cassidy was a servant of John Hutchins in Virginia in 1703.

Peter Cassity arrived later in the century.  His family moved onto Kentucky in the 1780’s.  Patrick Cassidy fought on the American side during the Revolutionary War and was granted land in Newry, Pennsylvania – which he named after his hometown in Ireland.

Many more Cassidys came in the 1840’s after the potato famine and again in the 1870’s and 1880’s.  These Cassidys settled for the most part in the Irish communities in Brooklyn.

Two sons of these immigrants did well:

  • Lewis Cassidy, who moved with his family to Philadelphia at an early age, studied law and later became Attorney General of Pennsylvania.
  • John Cassidy profited more fortuitously.   He was paid handsomely for standing in as a Civil War volunteer in place of the Spreckels sugar fortune heir.  He invested his money in cottages on Shelter Island, a place which later became a fashionable gathering spot for New York society. 

In the 20th century, from these roots, came the actor Jack Cassidy and his actor/singer son David Cassidy.  Daniel Cassidy, who grew up in a NY Irish neighborhood, compiled the 2007 best seller, How The Irish Invented Slang.

The Cassidy claIm to Wild West fame is mainly fictional.  Butch Cassidy of Butch Cassidy and the Sundance Kid was in fact born Robert Parker, the son of Irish immigrants from Lancashire.  Hopalong Cassidy was the fictional creation of Clarence Mulford.  But Neal Cassady, icon of the 1950’s Beat generation, had come from an Irish Quaker Casady family who had immigrated to America in the early 19th century.

Canada.  Early arrivals, in 1819, in St. John, New Brunswick were William and Jane Cassidy from Donegal. They settled in what is now called Cassidy Lake.  Although their original homestead has burnt down, there remain the foundations, apple orchards, cemetery and church that they built.

Patrick and Margaret Cassidy came from county Cavan in the 1820’s.  They later moved on to farm in Illinois.  Thomas Cassidy from West Meath appeared on the 1829 McCabe list of workers on the Rideau canal to connect Montreal with Toronto. He and his family stayed to farm in Wakefield township, Quebec.

New Zealand.  Thomas Cassidy from county Meath was one of the earliest arrivals into New Zealand.  He had been transported to Australia for seven years for stealing a pig.  After serving his term he embarked for New Zealand in 1829 and arrived in the north Auckland area where he married the daughter of a local Maori chief.  From this marriage have come a large number of descendants.

Hugh Cassidy from Donegal came to New Zealand in the 1860’s and ran hotels and a coach service from Hokitika on South Island for many years.  His son Michael ended up a lawyer and apparently a shrewd one, “charging exorbitant fees to those who could afford them and nominal ones to those who couldn’t.”

Cassidy Surname Miscellany

Ballycassidy.  The ancestral home of the Cassidys is Ballycassidy, which lies slightly north of Enniskillen, the principal city of County Fermanagh.  Ballycassidy borders the eastern shores of Lower Lough Erne.Today, it is a small rural community, consisting mainly of scattered homes, the Balcas sawmill and farm land along the Ballycassidy river.  There is no pub or grocery store.  In the fourteenth century, there was a church.  A nearby holy well is still marked on the map.

A Case of Cassidy Retribution.  John Cassidy was born in Drumbar in County Donegal in 1802.  He married and was a small tenant farmer at Clogher with ten acres of land.  This family story recounts a tale of retribution during the famine years.

“When one of John’s sheep went missing during the first famine years in the early 1830’s, he undertook an extensive search of the locality.  He eventually found the horns of the animal that had his markings at the rear of a cottage rented by a woman known as widow Kelly.  

Mrs. Kelly had two sons who spent their time stealing from their neighbors.  When John Cassidy confronted them, they denied having any involvement in the disappearance of the animal.  Shortly afterwards, the Kelly family decided to emigrate to America.  The day before they were leaving, the Kelly brothers paid a visit to John Cassidy’s home where they proceeded to give him a terrible beating that left him confined to bed for a number of weeks.  

In the spring of 1838, John Cassidy’s oldest son, also called John, boarded the Zephyr anchored at the Hassins in Donegal Bay and sailed to New Brunswick, Canada.  From there, he made his way to New York where the Kelly family were living.  One morning, as one of the Kelly brothers was standing on a railway station platform, he failed to notice his former neighbor standing behind him.  John Cassidy pushed him in front of the train.  He died instantly.” 

William and Jane Cassidy at Cassidy Lake.  The oldest of ten children, William was born in The Port near Donegal Town in 1797.  His wife Jane Milligan was also born there.   The story goes that they eloped in 1818 to Gretna Green in Scotland.  The village blacksmith performed the wedding ceremony over an anvil.  After the marriage, Jane, whose family were upper class land owners, was disowned by her family.

A year later, William and Jane went to Derry where they took a ship to Canada, landing at St. John’s in New Brunswick.  In 1825, they moved to a 150 acre parcel of land on the north side of what is now known as Cassidy Lake.  William had to walk a distance of 100 miles to Fredericton, the capital of the province, to acquire the land.  He did this in the winter when the rivers and lakes were frozen so that he could cross them.  With only a primitive compass and a gun to protect him, he undertook the journey through the forests.

The lifestyle of William and Jane was typical of a farm family of that period.  Candles made of tallow, salvaged and remolded continually, supplied light for their home.  Cast iron pots hooked on iron cranes were used for cooking over the fire. For bread, they grew and ground the wheat and baked the bread in a cast iron dish buried in the bed of coals at the bottom of the fireplace.  The family’s clothing was made from homespun cloth woven on hand looms.  William was a master craftsman in the making of these hand looms. 

Reader Feedback – Kyran Cassidy in New York.  I am looking for information on Kyran Cassidy. He would have been born in Ireland around 1824. By 1841 he was married and in New York. There is evidence of two sisters, Bridget and Catherine.  

Bridget (

Cassidy Births in Brooklyn, 1840-1850

Records at St. Peter, Paul, and Our Lady of Pilar

Birth Date Given Name Parents
1840 Andrew Charles and Johanna
1843 Susanna Pat and Susanna
1844 Margaret John and Mary
1845 John Edward and Catherine
1845 Peter James and Mary
1845 William Pat and Susanna
1846 Mary John and Mary
1849 William James and Mary

Records at Assumption Roman Catholic Church

Birth Date Given Name Parents
1845 Ann Bernard and Ellen
1847 Marica Bernard and Ellen
1850 Hugh Bernard and Ellen

James Rice Cassidy.  James Rice Cassidy left Scotland in the late 1880’s and headed for England to pursue a career in the entertainment business.  In 1895, he married a twenty one year old Yorkshire lass at St. Anne’s Church in Leeds.  On their marriage certificate he gave his occupation as “comedian.”  His wife Lillian was an actress and together they formed their own theater company.  They were a double act and she most definitely was an equal partner in the business.

James and Lillian toured all over Britain performing their own productions.  Their careers seemed to be going from strength to strength.  He was the son of a poor Irish plasterer, making a name for himself in show business – the classic rags to riches story!

One of their biggest successes was The God of War by Charles Whitlock.  It was performed in theaters throughout Scotland and England from 1899 to 1909.  The play was a satirical piece about the Cuban insurrection and the Spanish American War of 1895.  His character was Dandy Donovan, an Irish American servant to Dolly Daly an American heiress, played of course by Lillian.  In the play he sings his own composition called “The British Hero.”  The Glasgow Evening Times of April 7, 1901 called the play “a sensational Cuban American drama.”

Cassidy Names

  • Giolia Mochuda Mor Ó Caiside was an early bardic poet of Ireland. 
  • Ruaidhri Ó Caiside (Rory O Cassidy) was archdeacon of Clogher Cathedral in the early 1500’s.   
  • Thomas Cassidy, an expelled Augustinian friar and later soldier of fortune, wrote a racy autobiography which was popular in Ireland in the eighteenth century. 
  • Lewis Cassidy rose to become the Attorney General of Pennsylvania in the 1880’s.   
  • Con Cassidy was one of the great Donegal fiddle players of the 20th century. 
  • Cardinal Edward Cassidy, born in Australia, was one of the leading Vatican emissaries in the late 20th century. 
  • David Cassidy of New York Irish roots is an American actor, singer, and guitarist. 

Cassidy Numbers Today

  • 21,000 in the UK (most numerous in Lanarkshire)
  • 8,500 in America (most numerous in New York).
  • 18,000 elsewhere (most numerous in Canada) 

Cassidy and Like Surnames 

The Irish clan or sept names come through the mists of time until they were found in Irish records such as The Annals of the Four Masters.  The names were Gaelic and this Gaelic order was preserved until it was battered down by the English in the 1600’s.

Some made peace with the English.  “Wild geese” fled to fight abroad.  But most stayed and suffered, losing land and even the use of their language.  Irish names became anglicized, although sometimes in a mishmash of spellings.  Mass emigration happened after the potato famine of the 1840’s.

Some surnames – such as Kelly, Murphy and O’Connor – span all parts of Ireland.  But most will have a territorial focus in one of the four Irish provinces – Leinster, Munster, Ulster, and Connacht.

Ulster in NE Ireland covers the counties of Derry, Antrim, Down, Tyrone, Armagh, Fermanagh, Cavan, Monaghan, and Donegal.  Here are some of the Ulster surnames (excluding the Scots Irish surnames) that you can check out.


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Written by Colin Shelley

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