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

O'Shaughnessy, 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 O'Shaughnessy surname is from the 2010 census data.

Popularity of O'Shaughnessy in America

O'Shaughnessy is the 9940th most popular name in America based on the data we have collected from the U.S. Census Bureau.

The O'Shaughnessy surname appeared 3,246 times in the 2010 census and if you were to sample 100,000 people in the United States, approximately 1 people would have the surname O'Shaughnessy.

We can also compare 2010 data for O'Shaughnessy 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 O'Shaughnessy

The surname O'Shaughnessy is of Irish origin and can be traced back to the 12th century. It is derived from the Gaelic name 'Ó Seaghnaigh', which means 'descendant of Seaghanach'. The name Seaghanach itself is believed to have originated from the old Irish word 'seangan', meaning 'ant'.

The O'Shaughnessys were a prominent family in County Galway, Ireland, and their ancestral homeland was located in the ancient territory known as Cenél Áedha or Kinelea. This area encompassed parts of modern-day County Galway and County Roscommon. The name is also associated with the Baronies of Kinelea and Longford in County Galway.

One of the earliest recorded instances of the name O'Shaughnessy appears in the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the 17th century. The annals mention an Aedh O'Shaughnessy who was slain in 1237 during a conflict between rival Irish clans.

In the 16th century, the O'Shaughnessy family was prominent in the region and held significant landholdings. Notable members from this period include Sir Roebuck O'Shaughnessy (c. 1566-1635), who was knighted by King James I of England, and his son Sir Roger O'Shaughnessy (c. 1600-1670), who served as a Colonel in the Irish Confederate Wars.

During the 17th and 18th centuries, the O'Shaughnessy name can be found in various legal documents and land records in County Galway. Some variations in spelling include O'Shaughnussey, O'Shaughnessy, and O'Shanecy.

In more recent history, several notable individuals have borne the O'Shaughnessy surname. These include Arthur O'Shaughnessy (1844-1881), an English poet known for his work "Ode" and his connections to the Pre-Raphaelite movement. Another prominent figure was Sir William O'Shaughnessy (1809-1889), an Irish physician who served as the Director-General of Telegraph Operations in British India and made significant contributions to the field of telegraphy.

Other notable O'Shaughnessys include Eliza O'Shaughnessy (1829-1900), an Irish-American religious leader and founder of the Sisters of Providence; Michael O'Shaughnessy (1864-1934), an Irish-American civil engineer who oversaw the construction of the Hetch Hetchy Reservoir in California; and James O'Shaughnessy (1810-1889), an Irish-American lawyer and politician who served as the United States Secretary of the Interior under President James Buchanan.

Race and ethnic origin of people with the last name O'Shaughnessy

We also have some data on the ancestry of people with the surname O'Shaughnessy.

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 O'Shaughnessy 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 O'Shaughnessy 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 O'Shaughnessy was researched and written by our team of onomatology and genealogy experts.

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

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