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

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

Popularity of O'Callahan in America

O'Callahan is the 56310th most popular name in America based on the data we have collected from the U.S. Census Bureau.

The O'Callahan surname appeared 363 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'Callahan.

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

The surname OCALLAHAN is of Irish origin, originating in the historic Gaelic kingdom of Ulster in the northern part of Ireland. The name is an anglicized form of the Irish Gaelic "Ó Callanáin", which means "descendant of Callanán". Callanán is itself a diminutive form of the Irish name Cállán, derived from the word "cállan" meaning "little wolf" or "little battle leader".

The earliest recorded instances of the name can be traced back to the 16th century, when it was rendered in various spellings such as O'Callanane, O'Callanan, and O'Callinane. These early forms of the name were primarily found in County Donegal and County Tyrone, where the family held lands and positions of influence.

One of the earliest records of the name is in the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the early 17th century. The annals mention an OCALLAHAN family member named Donnchadh Ó Callanáin, who was a prominent poet and historian in the late 16th century.

In the 17th century, the name appears in various land and rent rolls, indicating the family's continued presence in Ulster. One notable figure from this period was Turlough OCALLAHAN, a landowner and military commander who fought for the Irish Catholic Confederacy during the Irish Confederate Wars of the 1640s.

The 18th century saw the OCALLAHAN name spread beyond Ulster, as members of the family migrated to other parts of Ireland and further afield. In 1798, during the Irish Rebellion, a man named Patrick OCALLAHAN was recorded as a rebel leader in County Wexford, demonstrating the family's involvement in the struggle for Irish independence.

The 19th century brought several OCALLAHAN individuals of note, including the scholar and historian John OCALLAHAN (1805-1880), who wrote extensively on Irish language and literature, and the celebrated poet and songwriter Denny OCALLAHAN (1838-1912), whose works celebrated Irish culture and identity.

Throughout its long history, the OCALLAHAN surname has maintained its connection to its Irish roots, with many bearers of the name contributing to the preservation and promotion of Irish heritage and culture across generations.

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

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

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'Callahan 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'Callahan 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'Callahan 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'Callahan, please contact us.

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