Find out how popular the last name O'Mahony 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'Mahony.

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

Popularity of O'Mahony in America

O'Mahony is the 31656th most popular name in America based on the data we have collected from the U.S. Census Bureau.

The O'Mahony surname appeared 730 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 O'Mahony.

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

The surname OMAHONY is an anglicized version of the original Irish Gaelic O'Mathghamhna, which translates to "descendant of the bear-like one". It originated in County Cork, Ireland, and can be traced back to the 10th century.

This surname is derived from the Irish personal name Mathghamhain, which means "bear" or "bear-like". The prefix "O'" indicates a male descendant of the original bearer of the name. The earliest recorded instance of this surname dates back to the 11th century, when it was spelled as O'Mathghamhna in the Annals of Inisfallen, a chronicle of medieval Irish history.

During the medieval period, the OMAHONY clan was based in the baronies of Ivahagh and Kinalmeaky in County Cork. They were a prominent Gaelic family and held substantial lands in the region. The name is mentioned in the Annals of the Four Masters, a chronicle of Irish history compiled in the early 17th century.

One of the earliest known individuals with this surname was Diarmaid O'Mathghamhna, a powerful chieftain who lived in the 12th century. He is recorded as leading forces against the Anglo-Norman invaders during the Norman conquest of Ireland.

Another notable figure was Conchobhar OMAHONY, who served as the Bishop of Cork and Cloyne from 1496 to 1503. He played a significant role in the ecclesiastical affairs of the region during his tenure.

In the 16th century, the OMAHONY clan faced challenges due to the Tudor conquest of Ireland. Many members of the clan lost their lands and were forced into exile. However, some descendants continued to hold onto their ancestral territories in County Cork.

One of the most famous individuals with this surname was Donal OMAHONY, an Irish soldier and military leader who fought in the Irish Confederate Wars of the 1640s. He was a prominent commander in the Irish Confederation's forces and played a crucial role in several battles against the English Parliamentarian forces.

During the 18th and 19th centuries, the OMAHONY surname spread throughout Ireland and beyond, with many individuals emigrating to other parts of the world, including the United States, Canada, and Australia.

Overall, the surname OMAHONY has a rich history rooted in the Gaelic heritage of County Cork, Ireland, and has been borne by several notable individuals throughout the centuries.

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

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

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'Mahony 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'Mahony 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'Mahony 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'Mahony, please contact us.

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