The history of your name

The OBRIEN surname in the USA

Frequency Comparisons
Total Rank Frequency % Per million people
United States
United States (Current snapshot) 115,385 234 0.043 428
United States (1880 census) 9,707 623 0.019 194
Change since 1880 +105678 +389 +0.024 +234
Other Countries
Australia 474 3368 0.003 29
United Kingdom 3,098 2006 0.007 67
Top States for OBRIEN by Total
State Total Rank in State Frequency % Per million people
New York 11,482 70 0.061 605
Massachusetts 11,042 16 0.174 1,739
California 9,551 286 0.028 282
Florida 7,472 208 0.047 468
Pennsylvania 6,236 128 0.051 508
Top States for OBRIEN by Frequency
State Total Rank in State Frequency % Per million people
Massachusetts 11,042 16 0.174 1,739
New Hampshire 1,442 42 0.117 1,167
Vermont 692 49 0.114 1,137
Rhode Island 1,002 48 0.096 956
Connecticut 3,102 47 0.091 911


'A figure of zero indicates that we don't have data for this name (usually because it's quite uncommon and our stats don't go down that far). It doesn't mean that there's no-one with that name at all!

For less common surnames, the figures get progressively less reliable the fewer holders of that name there are. This data is aggregated from several public lists, and some stats are interpolated from known values. The margin of error is well over 100% at the rarest end of the table!

For less common surnames, the frequency and "per million" values may be 0 even though there are people with that name. That's because they represent less than one in a million of the population, which ends up as 0 after rounding.

It's possible for a surname to gain in rank and/or total while being less common per million people (or vice versa) as there are now more surnames in the USA as a result of immigration. In mathematical terms, the tail has got longer, with a far larger number of less common surnames.

Figures for top states show firstly the states where most people called OBRIEN live. This obviously tends to be biased towards the most populous states. The second set of figures show where people called OBRIEN represent the biggest proportion of the population. So, in this case, there are more people called OBRIEN in New York than any other state, but you are more likely to find a OBRIEN by picking someone at random in Massachusetts than anywhere else.

Classification and Origin of OBRIEN

Region of origin: British Isles

Country of origin: Ireland

Language of origin: Gaelic

Ethnic origin: Celtic

Religious origin: Christian

Name derivation: From name of parent

Data for religion and/or language relates to the culture in which the OBRIEN surname originated. It does not necessarily have any correlation with the language spoken, or religion practised, by the majority of current American citizens with that name.

Data for ethnic origin relates to the region and country in which the OBRIEN surname originated. It does not necessarily have any correlation with the ethnicity of the majority of current American citizens with that name.

Ethnic distribution of OBRIEN in the USA

Classification Total Percent
Asian/Pacific 612 0.53
Native American/Alaskan 381 0.33
White (Caucasian) 109,973 95.31
Black/African American 1,304 1.13
Mixed Race 1,362 1.18
White (Hispanic) 1,754 1.52

Ethnic distribution data shows the number and percentage of people with the OBRIEN surname who reported their ethnic background as being in these broad categories in the most recent national census.

Meaning of OBRIEN in historical publications

O'BRIEN. The O'Briens of Tliomond took their name from the monarch Brian Boru, who was slain at the battle of Clontarf in 1014. 0"Douovan.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.

Similar names to OBRIEN

The following names have similar spellings or pronunciations as OBRIEN.

This does not necessarily imply a direct relationship between the names, but may indicate names that could be mistaken for this one when written down or misheard.

Matches are generated automatically by a combination of Soundex, Metaphone and Levenshtein matching.

Potential typos for OBRIEN

The following words are slight variants of OBRIEN that are likely to be possible typos or misspellings in written material.