2000
#17,702
National surname rank
Recorded bearers 1,460
First available Census row
Per 100,000 0.54
Rare Last name
Casimir
Derived from the Slavic element "kaziti" meaning "to destroy," referring to someone who destroys peace or is a military leader.
According to the 2020 US Census Bureau surname tables, roughly 2,548 Americans carry the last name Casimir. That puts it at #13,182 in the national surname ranking, appearing at a frequency of 0.74 per 100,000 people (about 1 in 134,519 residents).
This page is the full Name Census profile for the Casimir surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
For British records, Name Census UK has a British surname profile for Casimir with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
2.5K
1 in 134,519
Census rank
#13,182
2020 decennial data
Per 100,000
0.7
Frequency rate
Recorded bearers
2.2K
rare in the US
Popularity narrative
The Census Bureau recorded 2,222 bearers of the surname Casimir in its 2020 decennial surname file. At a rate of 0.74 per 100,000 residents, it holds the 13182nd position in the national surname ranking.
Among Census respondents with the surname Casimir, the largest self-reported group is Black at 79.9%. The next largest groups are White (10.3%) and Hispanic (5.1%).
Origin
Meaning and origin of Casimir
The surname Casimir originated from the Polish regions, with its roots tracing back to the 12th century. It is derived from the Old Polish word "Kazimierz," which means "to destroy peace" or "to destroy harmony." This name was originally a title or epithet bestowed upon a historical figure known for his warlike exploits or disruptive actions.
One of the earliest documented references to the name Casimir can be found in the chronicles of the Polish monarchy, where it was used to describe a prince or ruler who was renowned for his military conquests and territorial expansions. The name gained popularity among the nobility and eventually became a hereditary surname, passed down through generations of Polish families.
In the 13th century, a prominent figure named Casimir I, also known as Casimir the Restorer, ruled as the Grand Duke of Poland from 1034 to 1058. His reign was marked by the restoration of the Polish kingdom after a period of political turmoil, and he is widely regarded as one of the most influential rulers in Polish history.
Another notable bearer of the surname Casimir was Casimir III, also known as Casimir the Great, who reigned as the King of Poland from 1333 to 1370. He is celebrated for his efforts in strengthening the Polish economy, promoting education, and expanding the territory of the kingdom through diplomatic means.
In the 15th century, the surname Casimir was recorded in the annals of the Teutonic Knights, a Catholic military order that played a significant role in the Northern Crusades and the colonization of Prussia. A knight named Casimir von Liebenstein is mentioned in these records, having participated in various military campaigns and battles.
During the Renaissance period, a Polish nobleman named Casimir Jagiellończyk, born in 1458, gained prominence as a patron of the arts and a supporter of the humanist movement. He was instrumental in the establishment of several educational institutions and the promotion of cultural exchange within Europe.
In the 17th century, Casimir Leski, a Polish mathematician and astronomer, made significant contributions to the field of astronomy. He is best known for his work on celestial mechanics and his calculations of planetary orbits, which helped advance the understanding of the motions of celestial bodies.
These are just a few examples of notable individuals who bore the surname Casimir throughout history. The name has since spread beyond its Polish origins and can be found in various parts of the world, reflecting the migrations and cultural exchanges that have occurred over the centuries.
Demographics
Ancestry and ethnicity for Casimir
Among Census respondents with the surname Casimir, the largest self-reported group is Black at 79.9%. The next largest groups are White (10.3%) and Hispanic (5.1%).
The bar chart below shows how Casimir bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Casimir surname at the time of the 2020 Census, not any inherent property of the name itself.
- Black or African American79.9% · 1,775
- White10.3% · 229
- Hispanic or Latino5.1% · 114
- Two or more races3.3% · 73
- Asian and Pacific Islander0.9% · 19
- American Indian and Alaska Native0.5% · 12
Timeline
Historical Census data for Casimir
Casimir appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#15,217
National surname rank
Recorded bearers 1,936
+476 bearers (+32.6%)
Per 100,000 0.66
Rank movement Up 2,485 places
2020
#13,182
National surname rank
Recorded bearers 2,222
+286 bearers (+14.8%)
Per 100,000 0.74
Rank movement Up 2,035 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #17,702 | 1,460 | 0.54 | First available Census row | First available Census row |
| 2010 | #15,217 | 1,936 | 0.66 | +476 bearers (+32.6%) | Up 2,485 places |
| 2020 | #13,182 | 2,222 | 0.74 | +286 bearers (+14.8%) | Up 2,035 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Casimir surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #15,217 | #13,182 | 13.4% |
| Count | 1,936 | 2,222 | 14.8% |
| Per 100K | 0.66 | 0.74 | 12.6% |
Between the 2010 and 2020 Census, the number of Casimir bearers went from 1,936 to 2,222 (+14.8% change). The surname moved up 2,035 positions in the national ranking, going from #15,217 to #13,182.
FAQ
Casimir surname: questions and answers
How many people in the U.S. have the surname Casimir?
Name Census estimates that about 2,548 living Americans carry the surname Casimir. Using the current population baseline, that works out to roughly 1 in 134,519 residents.
How common is Casimir?
Casimir ranks #13,182 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.74 per 100,000 residents, which is about 1 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 2,222 people with the surname Casimir. That is different from the site's living-bearer estimate (2,548), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.74 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.74 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 1 of them to have the surname Casimir.
Has Casimir become more or less common over time?
Between 2010 and 2020, the surname Casimir went from 1,936 recorded bearers to 2,222. That is an increase of 286 (+14.8%). In the national ranking it rose from #15,217 to #13,182.
What does the Census say about the background of Casimir?
Among Census respondents with the surname Casimir, the largest self-reported group is Black at 79.9%. The next largest groups are White (10.3%) and Hispanic (5.1%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
Black is the largest self-reported group for the surname Casimir in the 2020 Census, accounting for 79.9% (1,775 people in the source table).
What is the full ancestry breakdown?
Casimir appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Black (79.9%), White (10.3%), Hispanic (5.1%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Casimir (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Casimir mean?
Derived from the Slavic element "kaziti" meaning "to destroy," referring to someone who destroys peace or is a military leader. The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Casimir (0.74 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How many people share the surname Casimir?
For a quick modern estimate, our sister site HowManyOfMe.org answers that in one glance, with the living-bearer count front and centre.