Cassidy Family History & Genealogy

20,617 biographies and 69 photos with the Cassidy last name. Discover the family history, nationality, origin and common names of Cassidy family members.

Cassidy Last Name History & Origin

Updated Feb 27, 2022


Cassidy is an Irish last name, made popular in large thanks to "Butch Cassidy & the Sundance Kid". The name Cassidy is taken from the Gaelic O'Caiside, meaning 'curly headed'.


The surname Cassidy, as far as is known, originated in Ireland hundreds of years ago. The family originated from Fermanagh and the surrounding counties.

According to some research, the Cassidy name goes back to 11th century doctors, and to the Irish chief McGuires. They were historians writing the history of Ireland in their native language. These writings are called the Annuals of Ulster (Irish: Annála Uladh).

One wrote the scientific manuscript depicting the many herbs of the day for healing. How and when to pick and prepare them. History, poetry, literature, religion law, continue to this day. Standing for justice the underdog , politics.

Name Origin

Gaelic O'Caiside means 'curly headed'.

Spellings & Pronunciations

Cassidy is pronounced as "Ca-city". Some variants include Cassedy and Kassidy.

Nationality & Ethnicity

Cassidy originated in the country of Ireland, which was once part of the United Kingdom.

  Cassidy is an Irish surname.

Famous People named Cassidy

David Cassidy, born in New York City, New York on April 12, 1950

Early Cassidies

These are the earliest records we have of the Cassidy family.


Cassidy Death Records & Life Expectancy

The average age of a Cassidy family member is 66.4 years old according to our database of 13,241 people with the last name Cassidy that have a birth and death date listed.


Other Cassidy Records


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Michelle Cassidy commented on Mar 14, 2006
As a young person, I find that I take genealogy for granted. This was until I found AncientFaces. Hearing other success stories made me want to discover and share a little more about my own ancestry. During my first search for information on the surname Cassidy, I found that I share lineage with former President Bill Clinton! His mother's maiden name was Virginia Dell Cassidy. President Clinton, whose father died before he was born, lived with his maternal grandparents for several years as a child while his mother attended nursing school. President Clinton credits his grandfather, James Eldridge Cassidy, with instilling in him a love for learning and teaching him to read by age four. Just an interesting tidbit I wanted to share. :)
Bonnie Schuring commented on Sep 19, 2019
My Cassidy family started in Fredericton New Brunswick Nova Scotia, another words Canada. My two times great grandmother Mary Jane Cassidy married Nahum foster in Canada. She was born in 1834, I believe her father was James Cassidy and her mother was Flora Patterson. They lived in Winnebago county Illinois, They had 11 children, two died in infancy their 1 surviving son died at 16 years of age, and another daughter died at age 25 leaving five children. My great grandmother Georgianna Foster was her fifth daughter. I would love to have more information on the Cassidy side in Canada, and her mother Flora Patterson was born in Scotland.
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