2000
#124,109
National surname rank
Recorded bearers 128
First available Census row
Per 100,000 0.05
Very Rare Last name
Rosaaen
A Scandinavian surname derived from a place name containing the elements "ros" (rose) and "aaen" (river or stream).
According to the 2020 US Census Bureau surname tables, roughly 114 Americans carry the last name Rosaaen. That puts it at #156,005 in the national surname ranking, appearing at a frequency of 0.03 per 100,000 people (about 1 in 3,006,617 residents).
This page is the full Name Census profile for the Rosaaen 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.
Bearers in the US
114
1 in 3,006,617
Census rank
#156,005
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
99
very rare in the US
Popularity narrative
The Census Bureau recorded 99 bearers of the surname Rosaaen in its 2020 decennial surname file. At a rate of 0.03 per 100,000 residents, it holds the 156005th position in the national surname ranking.
Among Census respondents with the surname Rosaaen, the largest self-reported group is White at 97.0%. The next largest groups are American Indian/Alaska Native (2.0%) and Two or More Races (1.0%).
Origin
Meaning and origin of Rosaaen
The surname ROSAAEN originated in Norway during the late medieval period, around the 13th or 14th century. It is believed to have derived from a combination of the Old Norse words "ross" and "aaen", which translate to "horse" and "river" or "stream", respectively. This suggests that the name may have initially referred to someone who lived near a river or stream where horses were commonly found or used for transportation.
One of the earliest recorded instances of the ROSAAEN surname can be traced back to a village in the Østfold county of southeastern Norway, where a family bearing this name is mentioned in historical records from the late 16th century. The village was situated near a river, lending credence to the theory of the name's origin.
In the 17th century, a notable figure named Hans ROSAAEN (1621-1689) was a prominent merchant and landowner in the city of Trondheim, which was then a major trading center in Norway. He is believed to have been one of the wealthiest individuals in the region at the time.
During the 18th century, the ROSAAEN name appeared in various church records and legal documents throughout Norway, indicating its spread across different regions of the country. One notable individual from this era was Ingrid ROSAAEN (1732-1801), a respected midwife and herbalist in the town of Skien.
In the 19th century, the ROSAAEN surname gained more prominence with the rise of industrialization and urbanization in Norway. Johan ROSAAEN (1826-1892) was a successful businessman and one of the founders of the Rosaaen Textile Mill, which became a major employer in the city of Bergen.
Another significant figure was Knut ROSAAEN (1854-1923), a renowned architect who designed several churches and public buildings throughout Norway, including the iconic Trondheim Cathedral. His work was instrumental in shaping the architectural landscape of the country during that period.
As Norway experienced increased emigration to other parts of the world, particularly the United States and Canada, the ROSAAEN surname began to spread globally. However, the majority of individuals bearing this name can still trace their roots back to Norway and its various regions.
Demographics
Ancestry and ethnicity for Rosaaen
Among Census respondents with the surname Rosaaen, the largest self-reported group is White at 97.0%. The next largest groups are American Indian/Alaska Native (2.0%) and Two or More Races (1.0%).
The bar chart below shows how Rosaaen 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 Rosaaen surname at the time of the 2020 Census, not any inherent property of the name itself.
- White97.0% · 96
- American Indian and Alaska Native2.0% · 2
- Two or more races1.0% · 1
Timeline
Historical Census data for Rosaaen
Rosaaen 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
#133,048
National surname rank
Recorded bearers 127
-1 bearers (-0.8%)
Per 100,000 0.04
Rank movement Down 8,939 places
2020
#156,005
National surname rank
Recorded bearers 99
-28 bearers (-22.0%)
Per 100,000 0.03
Rank movement Down 22,957 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #124,109 | 128 | 0.05 | First available Census row | First available Census row |
| 2010 | #133,048 | 127 | 0.04 | -1 bearers (-0.8%) | Down 8,939 places |
| 2020 | #156,005 | 99 | 0.03 | -28 bearers (-22.0%) | Down 22,957 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 Rosaaen 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 | #133,048 | #156,005 | -17.3% |
| Count | 127 | 99 | -22.0% |
| Per 100K | 0.04 | 0.03 | -17.2% |
Between the 2010 and 2020 Census, the number of Rosaaen bearers went from 127 to 99 (-22.0% change). The surname moved down 22,957 positions in the national ranking, going from #133,048 to #156,005.
FAQ
Rosaaen surname: questions and answers
How many people in the U.S. have the surname Rosaaen?
Name Census estimates that about 114 living Americans carry the surname Rosaaen. Using the current population baseline, that works out to roughly 1 in 3,006,617 residents.
How common is Rosaaen?
Rosaaen ranks #156,005 in the 2020 Census surname tables and is classified on this site as "Very Rare." The Census recorded the name at a frequency of 0.03 per 100,000 residents, which is about 0 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 99 people with the surname Rosaaen. That is different from the site's living-bearer estimate (114), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.03 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.03 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 0 of them to have the surname Rosaaen.
Has Rosaaen become more or less common over time?
Between 2010 and 2020, the surname Rosaaen went from 127 recorded bearers to 99. That is a decrease of 28 (-22.0%). In the national ranking it fell from #133,048 to #156,005.
What does the Census say about the background of Rosaaen?
Among Census respondents with the surname Rosaaen, the largest self-reported group is White at 97.0%. The next largest groups are American Indian/Alaska Native (2.0%) and Two or More Races (1.0%). 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?
White is the largest self-reported group for the surname Rosaaen in the 2020 Census, accounting for 97.0% (96 people in the source table).
What is the full ancestry breakdown?
Rosaaen appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (97.0%), American Indian/Alaska Native (2.0%), Two or More Races (1.0%). 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 Rosaaen (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 Rosaaen mean?
A Scandinavian surname derived from a place name containing the elements "ros" (rose) and "aaen" (river or stream). 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 Rosaaen (0.03 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 are called Rosaaen?
See how many people have the last name Rosaaen on HowManyOfMe.org, our sister site built around that single question.