Mamoru
To protect or defend; a masculine Japanese name.
Name Census estimates that about 8 living Americans carry the first name Mamoru. The name is used almost exclusively for boys. The average person named Mamoru today is around 100 years old, and the year with the single highest number of Mamoru births was 1924 (16 babies).
This page is the full Name Census profile for Mamoru. Below you will find a gender breakdown showing how the name splits between male and female registrations, a year-by-year popularity chart stretching back to 1880, decade-level totals, the top US states for this name, its meaning and etymology, and a set of frequently asked questions with data-backed answers.
Key insights
- • The typical person named Mamoru is about 100 years old today, placing it firmly among the names of earlier generations. Most living Mamorus were born before 1936.
- • Fewer than 100 living Americans are believed to carry the name Mamoru. It is among the rarest names in the SSA records.
People living today
8
~ 1 in 42,844,292 Americans
Peak year
1924
16 babies that year
Average age
100
years old
1937 SSA rank
#3,843
Tracked since 1915
Census
Mamoru in the 2020 Census
The 2020 Census recorded 152 people with the first name Mamoru, which placed it at #44,992 in the published first-name tables. This is a snapshot of people who already had the name at the time of the Census.
The SSA sections elsewhere on this page answer a different question: how often parents gave the name to babies over time. The "people living today" figure on this page is different again: it is a current estimate built from SSA birth records and age-based survival rates, so the two numbers are not expected to match exactly.
2020 Census rank
#44,992
National first-name rank
People counted
152
152 in the published race/origin table
Per 100,000
0.1
People with this name in 2020
Largest reported group
Asian and Pacific Islander
91.4% of people with this name
Demographics
Ancestry and ethnicity for Mamoru
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Mamoru is Asian/Pacific Islander at 91.4%. The next largest groups are Two or More Races (3.9%) and Hispanic (2.0%). These figures describe the people who had the name in 2020, not any inherent property of the name itself.
The bar chart below shows how people with the first name Mamoru 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 name, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown so the breakdown is easy to read across every published category. Because the 2020 Census first-name file also includes raw headcounts for each group, Name Census can show those alongside the percentages in the legend and hover tooltip.
Keep in mind that these are self-reported numbers. A first name does not determine a person's race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the name Mamoru at the time of the 2020 Census, not any inherent property of the name itself.
- Asian and Pacific Islander91.4% · 139
- Two or more races3.9% · 6
- Hispanic or Latino2.0% · 3
- White1.3% · 2
- Black or African American1.3% · 2
Popularity
Mamoru: popularity over time
The SSA tracks Mamoru from the 1910s through to the 1930s, spanning 3 decades of birth certificate data. The biggest single decade for the name was the 1920s, with 116 total registrations. Usage has dropped considerably from its 1920s peak. The most recent decade brought in only a fraction of the registrations that the name once attracted.
Babies born per year
Decades
Mamoru by decade
The table below breaks the full SSA timeline into ten-year windows. Each row shows how many male and female babies were given the name Mamoru during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Geography
Where Mamorus live
Origin
Meaning and history of Mamoru
The name Mamoru is a Japanese given name that originates from the verb "mamoru," which means "to protect" or "to guard" in the Japanese language. This name has been in use for centuries in Japan, reflecting the cultural values of loyalty, honor, and the duty to safeguard others.
The earliest known reference to the name Mamoru can be traced back to the Heian period (794-1185 CE) in Japan. During this era, the name was often given to samurai warriors who were expected to protect their lords and the people under their care. The name also appears in several ancient Japanese literary works, such as the Genji Monogatari (The Tale of Genji), written in the early 11th century.
One of the most notable historical figures with the name Mamoru was Mamoru Chiba, a renowned Japanese swordsman and samurai who lived during the Sengoku period (1467-1615 CE). He was known for his exceptional swordsmanship and unwavering loyalty to his lord, Tokugawa Ieyasu. Another prominent individual was Mamoru Fukushima (1835-1912), a Japanese military officer and statesman who played a crucial role in the modernization of Japan's armed forces during the Meiji Restoration.
In the realm of literature, Mamoru Kaoru (1658-1704) was a celebrated Japanese poet and scholar who contributed significantly to the development of the haiku form. His works are still widely read and studied today. Additionally, Mamoru Shigemitsu (1887-1957) was a Japanese diplomat who served as the Minister for Foreign Affairs during the final years of World War II.
Moving into more recent history, Mamoru Mohri (1912-1992) was a highly respected Japanese ceramic artist and Living National Treasure of Japan, renowned for his innovative techniques and designs. Mamoru Hosoda (born 1967) is a contemporary Japanese film director and animator, best known for his critically acclaimed animated films such as "The Girl Who Leapt Through Time" and "Wolf Children."
Throughout its long history, the name Mamoru has consistently embodied the ideals of protection, loyalty, and honor, making it a popular choice for parents seeking to imbue these qualities in their children. Its enduring presence in Japanese culture reflects the deep-rooted traditions and values that have shaped the nation over centuries.
People
Mamoru + last name combinations
How many people share a full name with Mamoru as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with M
Other first names starting with M with a similar number of bearers.
FAQ
Mamoru: questions and answers
How many people in the U.S. are named Mamoru?
Name Census puts the figure at roughly 8 living Americans. We arrive at this by taking every SSA birth registration for Mamoru going back to 1880 and adjusting each cohort for expected survival using CDC actuarial life tables. The result is an age-weighted living-bearer count, not a raw birth total. That works out to about 1 in 42,844,292 US residents.
Is Mamoru a common name?
We classify Mamoru as "Very Rare". It ranks above 24.6% of all first names in the SSA dataset by living bearers. Across the full history of the data, 182 babies have been registered with this name.
When was Mamoru most popular?
The single biggest year for Mamoru was 1924, when 16 babies received the name. The fact that the average living Mamoru is about 100 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
How common was Mamoru in the 2020 Census?
The published 2020 Census first-name tables recorded 152 people with the name Mamoru, or 0.05 per 100,000 residents. That placed it at #44,992 in the national Census ranking for first names.
Why is the Census count different from the living estimate?
Because they measure different things. The Census figure is a count of people who had the name Mamoru in 2020. The living estimate aims to answer a current question instead: how many people with the name are alive today, based on SSA birth records and age-based survival rates. Since one number is a 2020 snapshot and the other is a present-day estimate, they are not expected to be identical.
What does the Census say about the gender split for Mamoru?
In the 2020 Census sex table, Mamoru appears almost entirely male. Of the 150 people counted with this name, 100.0% were male and only a very small share were female. The Census view is a snapshot of people living with the name in 2020, while the SSA section above tracks births across time.
What does the Census say about the background of people named Mamoru?
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Mamoru is Asian/Pacific Islander at 91.4%. The next largest groups are Two or More Races (3.9%) and Hispanic (2.0%). These figures describe the people who had the name in 2020, not any inherent property of the name itself. The percentages in the chart above come from self-reported race and Hispanic-origin responses in the 2020 Census.
Which group reports the name Mamoru most often in the Census?
Asian/Pacific Islander is the largest reported group for people named Mamoru in the 2020 Census, accounting for 91.4% (139 people in the published table).
Why can the Census sex total and race total differ slightly?
The Census Bureau published separate 2020 tables for sex and for race/Hispanic origin, and the released figures can differ slightly because of privacy protection in the public files. That is why this page treats the gender section and the race/origin section as two related snapshots instead of forcing them into one identical total.
Does every first name have Census demographic data?
No. The public Census first-name release only includes names that met the Bureau's publication rules, so many rarer names in the SSA files have no Census demographic snapshot. When that happens, the SSA trend, gender history, and state sections still appear, but the 2020 Census demographic sections are omitted.
What does the SSA popularity chart show?
The chart tracks births, not the number of people alive with the name today. Each point shows how many babies were given the name Mamoru in that year. That makes it useful for spotting when the name rose, peaked, or faded.
Is Mamoru a male name?
Yes, 100.0% of people registered as Mamoru in the SSA data are male. You can see the full per-sex comparison in the gender distribution section above, which includes the latest year rank, birth count, and peak year for each sex.
Is Mamoru still being used today?
Yes. The SSA still recorded Mamoru in 2024, and the page above shows its latest-year rank where available. A name can be well past its peak and still remain in steady use, especially if it built up a large population over earlier decades.
Why can a name have a lot of living bearers even if it is not trendy now?
Because living-bearer counts and current baby-name popularity measure different things. A name like Mamoru can build up a very large population over many decades, even if fewer parents are choosing it now than they did at its peak.
Where does this data come from?
First-name figures come from the Social Security Administration's national baby name files, which cover every name on a birth certificate from 1880 to 2024. Living-bearer estimates layer in CDC actuarial life tables broken out by sex to account for mortality. The population baseline (342,754,338) is the Census Bureau's latest national estimate. You can read the full calculation on our methodology page.
How common is the name Mamoru?
See how many people have the name Mamoru on HowManyOfMe.org, our sister site built around that single question.