Find out how popular the last name Fennessy is in the United States and learn more about the meaning, history, and race and ethnic origin of people in America who are named Fennessy.

Fennessy, like all of the last names we have data for, is identified by the U.S. Census Bureau as a surname which has more than 100 occurrences in the United States in the Decennial Census survey. The most recent statistics we have for the Fennessy surname is from the 2010 census data.

Popularity of Fennessy in America

Fennessy is the 26229th most popular name in America based on the data we have collected from the U.S. Census Bureau.

The Fennessy surname appeared 932 times in the 2010 census and if you were to sample 100,000 people in the United States, approximately 0 people would have the surname Fennessy.

We can also compare 2010 data for Fennessy to data from the previous census in 2000. The table below contains all of the statistics for both years in a side-by-side comparison.

The history of the last name Fennessy

The surname Fennessy originated in Ireland, deriving from the Gaelic name O'Fínnachta, which means "descendant of Fionnachta." Fionnachta was a personal name composed of the Gaelic elements "fionn," meaning fair or white, and "acht," meaning active or vigorous. The name initially emerged in County Cork during the Middle Ages.

Over time, the name evolved through various spellings, including O'Fennessie, Fennessie, Fennesy, and Fennessy. The earliest recorded instances of the name can be found in the Annals of Inisfallen, a chronicle of medieval Irish history, where the surname appears as "O'Finnachta" in entries dating back to the 12th century.

One of the earliest notable individuals with the Fennessy surname was Dermot O'Fennessie, a 16th-century Irish chieftain from County Cork. He is mentioned in the Annals of the Four Masters, a renowned historical chronicle compiled in the early 17th century.

In the 17th century, the Fennessy surname began to appear in records from County Limerick, suggesting that members of the family had established themselves in that region. One of the earliest recorded individuals from this area was John Fennesy, who was born around 1650 in Limerick.

During the 18th century, the name Fennessy gained recognition with the birth of John Fennessy (1719-1790), an Irish Catholic priest and educator who founded several schools in County Cork. He played a crucial role in promoting education during a time when it was heavily restricted for Catholics in Ireland.

Another notable individual with this surname was Michael Fennessy (1822-1901), an Irish-born Australian politician and businessman. He served as a member of the Victorian Legislative Assembly and was involved in various business ventures in the state of Victoria.

In the 19th century, the Fennessy surname also gained prominence in the United States, with individuals such as Patrick Fennessy (1832-1908), an Irish-American politician and businessman who served as the mayor of Memphis, Tennessee, from 1887 to 1889.

Throughout history, the Fennessy surname has been associated with various place names in Ireland, including Fennessycourt and Fennessy's Cross, both located in County Cork. These place names likely originated from prominent Fennessy families who resided in those areas.

Race and ethnic origin of people with the last name Fennessy

We also have some data on the ancestry of people with the surname Fennessy.

The below race categories are the modified race categories used in the Census Bureau's population estimates program. All people were categorized into six mutually exclusive racial and Hispanic origin groups:

1. White only
2. Black only
3. American Indian and Alaskan Native only
4. Asian and Pacific Islander only
5. Hispanic
6. Two or More Races

For the most recent 2010 census data, the race/ethnic origin breakdown for Fennessy was:

Note: Any fields showing (S) means the data was suppressed for privacy so that the data does not in any way identify any specific individuals.

Since we have data from the previous census in 2000, we can also compare the values to see how the popularity of Fennessy has changed in the 10 years between the two census surveys.

Data source

The last name data and ethnic breakdown of last names is sourced directly from the Decennial Census survey, conducted every 10 years by the United States Census Bureau.

The history and meaning of the name Fennessy was researched and written by our team of onomatology and genealogy experts.

If you have a correction or suggestion to improve the history of Fennessy, please contact us.

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