2000
#1,141
National surname rank
Recorded bearers 28,075
First available Census row
Per 100,000 10.41
Uncommon Last name
Gilliam
A surname of Irish origin, derived from the Gaelic "Mac Gille Eáin," meaning "son of the servant of John."
According to the 2020 US Census Bureau surname tables, roughly 32,155 Americans carry the last name Gilliam. That puts it at #1,233 in the national surname ranking, appearing at a frequency of 9.38 per 100,000 people (about 1 in 10,659 residents).
This page is the full Name Census profile for the Gilliam 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 Gilliam with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
32K
1 in 10,659
Census rank
#1,233
2020 decennial data
Per 100,000
9.4
Frequency rate
Recorded bearers
28K
uncommon in the US
Popularity narrative
The Census Bureau recorded 28,041 bearers of the surname Gilliam in its 2020 decennial surname file. At a rate of 9.38 per 100,000 residents, it holds the 1233rd position in the national surname ranking.
Among Census respondents with the surname Gilliam, the largest self-reported group is White at 58.8%. The next largest groups are Black (32.8%) and Two or More Races (4.6%).
Origin
Meaning and origin of Gilliam
The surname Gilliam is of English origin and dates back to the medieval era. It is derived from the personal name Giles, which in turn comes from the Greek name Aegidius, meaning "young goat." The Gilliam surname likely originated as a patronymic, meaning "son of Giles."
One of the earliest recorded instances of the surname Gilliam can be found in the Domesday Book of 1086, which was a comprehensive survey of land ownership in England commissioned by William the Conqueror. The name is listed as "Gilliam" and is believed to refer to landowners or tenants at the time.
In the 13th century, the surname appeared in various records with slightly different spellings, such as "Giliam," "Gillam," and "Gyllyam." These variations were common due to the inconsistencies in spelling during that period.
The Gilliam surname has been associated with several notable individuals throughout history. One of the earliest recorded bearers of the name was William Gilliam, a merchant and alderman in the city of London who lived in the late 14th century.
In the 16th century, the Gilliam family established themselves as landowners in the county of Dorset. One prominent member was Robert Gilliam (c. 1532-1603), a wealthy landowner and member of the gentry.
During the English Civil War in the 17th century, several Gilliams fought on both sides of the conflict. One notable figure was Captain John Gilliam (c. 1620-1684), a Royalist soldier who fought for King Charles I.
In the 18th century, the Gilliam family continued to be prominent in various parts of England. Benjamin Gilliam (1716-1794) was a successful merchant and landowner in the county of Gloucestershire.
The surname also found its way to the American colonies, where it was borne by several notable individuals. One of the most famous was Ezekiel Gilliam (1733-1784), a Virginia planter and military officer who served in the American Revolutionary War.
These are just a few examples of the many individuals who have borne the surname Gilliam throughout history. While the name may have originated from humble beginnings, it has been carried by people from various walks of life, including merchants, landowners, soldiers, and planters.
Demographics
Ancestry and ethnicity for Gilliam
Among Census respondents with the surname Gilliam, the largest self-reported group is White at 58.8%. The next largest groups are Black (32.8%) and Two or More Races (4.6%).
The bar chart below shows how Gilliam 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 Gilliam surname at the time of the 2020 Census, not any inherent property of the name itself.
- White58.8% · 16,481
- Black or African American32.8% · 9,200
- Two or more races4.6% · 1,303
- Hispanic or Latino2.8% · 780
- Asian and Pacific Islander0.5% · 146
- American Indian and Alaska Native0.5% · 131
Timeline
Historical Census data for Gilliam
Gilliam 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
#1,204
National surname rank
Recorded bearers 29,414
+1,339 bearers (+4.8%)
Per 100,000 9.97
Rank movement Down 63 places
2020
#1,233
National surname rank
Recorded bearers 28,041
-1,373 bearers (-4.7%)
Per 100,000 9.38
Rank movement Down 29 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #1,141 | 28,075 | 10.41 | First available Census row | First available Census row |
| 2010 | #1,204 | 29,414 | 9.97 | +1,339 bearers (+4.8%) | Down 63 places |
| 2020 | #1,233 | 28,041 | 9.38 | -1,373 bearers (-4.7%) | Down 29 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 Gilliam 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 | #1,204 | #1,233 | -2.4% |
| Count | 29,414 | 28,041 | -4.7% |
| Per 100K | 9.97 | 9.38 | -5.9% |
Between the 2010 and 2020 Census, the number of Gilliam bearers went from 29,414 to 28,041 (-4.7% change). The surname moved down 29 positions in the national ranking, going from #1,204 to #1,233.
Notable bearers
Famous people with the surname Gilliam
FAQ
Gilliam surname: questions and answers
How many people in the U.S. have the surname Gilliam?
Name Census estimates that about 32,155 living Americans carry the surname Gilliam. Using the current population baseline, that works out to roughly 1 in 10,659 residents.
How common is Gilliam?
Gilliam ranks #1,233 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 9.38 per 100,000 residents, which is about 9 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 28,041 people with the surname Gilliam. That is different from the site's living-bearer estimate (32,155), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 9.38 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 9.38 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 9 of them to have the surname Gilliam.
Has Gilliam become more or less common over time?
Between 2010 and 2020, the surname Gilliam went from 29,414 recorded bearers to 28,041. That is a decrease of 1,373 (-4.7%). In the national ranking it fell from #1,204 to #1,233.
What does the Census say about the background of Gilliam?
Among Census respondents with the surname Gilliam, the largest self-reported group is White at 58.8%. The next largest groups are Black (32.8%) and Two or More Races (4.6%). 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 Gilliam in the 2020 Census, accounting for 58.8% (16,481 people in the source table).
What is the full ancestry breakdown?
Gilliam appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (58.8%), Black (32.8%), Two or More Races (4.6%). 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 Gilliam (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 Gilliam mean?
A surname of Irish origin, derived from the Gaelic "Mac Gille Eáin," meaning "son of the servant of John." 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 Gilliam (9.38 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 common is the surname Gilliam?
Our sister site HowManyOfMe.org answers how many people have the last name Gilliam at a glance, with the living-bearer count up front.