Question: What % of white Americans have colonial roots?

[BWV]

I've read the Guardian article and I wonder if it is indeed the case that every living European (and thus white American) is a more or less direct descendant of Charlemagne, instead of just western European (e.g. British, French, German, Dutch, Belgian, etc.). For example, would, say, Finns, Ukrainians, or Polish people (who are European) be among those who are Charlemagne's descendants?

What about Ashkenazi Jews (i.e. descendants of Jews who settled in central and eastern Europe) -- given the tendency toward endogamy in that population, I would highly doubt that Charlemagne's genetic legacy (or of similar such heritage) could have entered into that community.

Certainly there were isolated populations - Jews (maybe), certainly fringe geographies like Laplanders or Basques etc that may be exceptions. But think about how many armies passed through Central Europe (including Poland and most of Eastern Europe) over the past 1000 years, from the Crusaders through Napoleon's Grand Armee raping just about every woman they got their hands on.

 

[Aufbauwerk 2045]

I debated with myself about answering. Then I decided that perhaps non-Americans or even Americans who do not understand our history will learn something valuable about our heritage.

I think I'm not a Mayflower descendant. One of my ancestors was named Warren, but I'm not sure he was related to the Mayflower Warren, or even to Pocahontas. (That's a bit of a joke, for those who follow the news.)

My earliest American ancestors date back to about 1635. They were all Puritans who came over on the Winthrop fleet during the Great Migration of 1630-1640. They settled Massachusetts, Connecticut, and Long Island, and later Vermont. They had enormous families. So I suppose there are many of us who are their descendants. I doubt most people are aware of how many Americans are cousins. For example, I discovered recently that I am a distant relation of Ron Paul and Rand Paul. We have some common Puritan ancestry going back to New England.

There is some interesting mathematics in this subject. A simple exercise reveals that if we go back enough generations, it becomes mathematically certain that many of our ancestors who show up in the family tree at separate nodes in the tree were identical. Otherwise, we would have had more distinct ancestors than the population of the Earth at the time.

Perhaps most people of my heritage who came over to America as settlers have "royal blood." That is because we are descended from fourth daughters of third sons and so on going back to Alfred the Great or William the Conqueror. What happened is that if your ancestors did not qualify for their place in the royal palace, and actually had to earn a living somehow, some of the men became wool merchants or Anglican clergymen, and some of the women married such men.

One problem with clergymen in 1630 was that if you were a Puritan, it was hard to find a job under Charles I, and you might even end up in prison, so you packed up your bags and moved your family to America. You could start a new church and be a Puritan there without getting into trouble.

One of my English ancestors was recruited by Winthrop to fortify Long Island. Before that he made his reputation as a military engineer, serving the Dutch army which was fighting the Spanish. He was involved in the very first Indian war fought by English against the natives. His family were actually friendly with the Indians in their area, and his son became perhaps the first Englishman to learn Algonquin. The natives were fighting each other, so some of them welcomed Europeans who would fight on their side.

The rest of my family is German. They came a bit later than the English. Unfortunately their part of Germany was ravaged by religious oppression, war, the plague, and poverty. In some cases their farms, workshops, and even their entire town had been destroyed by the French during the Thirty Years War. If you want to know more about the Thirty Years War, see the movie The Last Valley with Michael Caine and Omar Sharif. As bad as it seems in the movie, the reality was far worse.

There was a shorter war, not long after the end of the Thirty Years War, which began after enough orphan boys had grown up and could replace their deceased fathers in someone's army. That war, known as the War of the Grand Alliance, seems to have been the last straw for some of my ancestors from Germany, who settled in Pennsylvania. In one case that I know of, the French army had destroyed what was left of their village, leaving only the church and the town hall. The Germans had to flee and live in the woods until the French army departed.

Perhaps this makes it clear why so many Germans who lived near the French border decided to move from such a beautiful region to wild Pennsylvania. You can't eat scenery, and if you did have a farm, or a good livelihood from your craft, perhaps the French, or even other Germans, might rob you or destroy everything. Also, people were sick of religious wars, witch burnings, and torture, so they were looking for something different. William Penn promised religious freedom, along with land or employment as a craftsman. German farmers and craftsmen were in great demand. Penn sent agents to Germany to recruit them.

There were also a few ancestors from Switzerland. They fled Switzerland to Germany because at that time the Germans were not persecuting Mennonites as they were doing in Switzerland. My Mennonite ancestors were expelled from canton Bern by the Calvinists and threated with perhaps fatal consequences if they returned. I regard these people as Germans by choice, rather than as Swiss. One of them is buried today in Greisheim, a town in Hesse. I'm descended from his son, who emigrated to Pennsylvania.

During WWI some of my German ancestors changed their surname to sound more American, or at least more Dutch. They wanted to be accepted as 100% American. There was so much anti-German hysteria whipped up during that period by pro-British propagandists that in some school districts it was forbidden to teach German -- even though it was the main second language at that time for science students. Fortunately, I have studied German, so even though I missed out on speaking German as my native language within my family, I know it anyway. I could visit some of my distant Mennonite cousins in Pennsylvania and speak German with them, although they speak Pennsylvania Dutch, and I learned Hochdeutsch.

One could say that in those times the situation was suboptimal for many people. The same is true today. Otherwise, perhaps people would not move around so much. Who wants to move if your life is great where you are?

I admit to some envy when I meet people like a German girl I chatted with not too long ago. She grew up in the same house that had been in her family for several generations. She still lives there today.

 

[Chris Riccard]

I have family in the north (fathers side), mostly mass and family in VA (mothers side) even though I don't know any of my family by the looks of things and from what I understand I am English, French, german, irish, Italian and 1/16 American indian (Chesapeake). now my sister had one of those ancestry dna tests done and she says it came back half jewish. I am a mutt, but deep inside this is me( as a girl lol):

 

[Torbert]

My mom did family tree research back to a bastard son of Henry II. America reached in 1630.
Oklahoma by 1840. Alaska in 1908.
One fought in the american revolution, 'Return Jonathan' was born while his father was off to war.
In Oklahoma a great grandmother had a partial native american as a husband. Daughter 'Minnie' tried to fly from the roof of a barn with a pair of tightly held Turkey wings.

Of the forty generations of ancestors I am aware of, I have details of about ten. The other 99% are just faceless names.
My children are half native Alaskan and consider themselves to be Alaskan.
My father's history is shorter, four brothers left Norway in 1890. Got to Canada and Alaska 1914.

Considering the enormous variety I am pretty flexible. Cultural identity is not what it used to be.
I am not alone in this, cultural identity seems pretty confused for many of the contributors to this thread.

 

[russ_watters]

Considering the enormous variety I am pretty flexible. Cultural identity is not what it used to be.
I am not alone in this, cultural identity seems pretty confused for many of the contributors to this thread.

At risk of turning political on Martin Luther King day (still in some time zones...), cultural identity isn't supposed to be important anymore. It's interesting for personal reasons, but not terribly relevant in the grand scheme of things unless you are an anthropologist or... nevermind.

 

[Keith_McClary]

what percentage of white Americans are descended from those Europeans who arrived during the colonial period

If we had everyone's complete genealogy, we could figure out what percentage of each group everyone (alive today) is descended from, and take the average of "whites" (however defined). Would that be a precise statement of what you're asking?
Of course we don't have complete genealogy, but the percentages could be estimated.

 

[StatGuy2000]

If we had everyone's complete genealogy, we could figure out what percentage of each group everyone (alive today) is descended from, and take the average of "whites" (however defined). Would that be a precise statement of what you're asking?
Of course we don't have complete genealogy, but the percentages could be estimated.

That would be an interesting exercise to conduct to determine such a percentage.

I can think of a few other ways to determine such percentages:

1. Conduct a survey of white Americans and ask how they identify themselves ethnically, or ask them when their family arrived in America. I would bet that those who are descended from European immigrants arriving from the 19th and 20th centuries would self-identify as an "ethnic" American (e.g. Irish-American, Italian-American, Polish-American). The exception would be those who immigrated from England in the 19th or 20th centuries, who would simply melt into the mainstream American identity.

2. Determine where geographically the white American families have their roots. For example, southern white Americans (i.e. those who come from the antebellum Southern states) are overwhelmingly descended from English, Scottish, and Northern Irish colonists who arrived during the 17th and 18th centuries, except for those from Louisiana (who are descended from French colonists who arrived during the 17th and 18th centuries). Ditto for those of old stock Yankees from the New England states (e.g. Maine, New Hampshire, Vermont, Connecticut).

 

[gmax137]

For example, southern white Americans (i.e. those who come from the antebellum Southern states) are overwhelming descended from English, Scottish, and Northern Irish colonists who arrived during the 17th and 18th centuries,

I think this might have been true 100 years ago but today, not so much. People move around a lot in the past 25 - 50 years. Have you been to Raleigh NC lately, or Richmond, VA, or Birmingham AL etc.?

 

[StatGuy2000]

I think this might have been true 100 years ago but today, not so much. People move around a lot in the past 25 - 50 years. Have you been to Raleigh NC lately, or Richmond, VA, or Birmingham AL etc.?

When I refer to southern white Americans, I'm obviously referring to those with deep roots in the state, as opposed to more recent arrivals. The emphasis is on the word "deep".

You are correct that Raleigh, NC is very diverse (I've visited the city on business a few years ago, btw), but I would bet that the white Americans living in the more rural areas of North Carolina would be far more homogeneous and likely descended from the original British settlers who arrived there during the 17th and 18th centuries.

I would imagine it would be similar in both Virginia (or at least areas of Virginia more distant from Washington, D.C., particularly the more rural areas) and Alabama. Although admittedly I don't have data to back this up.

 

[BillTre]

I don't think that human conjecture (or family histories) provide dependable information on this.

It is my understanding that sequence studies have shown a lot of people don't have realistic understanding of their own ethnic background.
There are amusing stories of racists that have backgrounds among those they disparage.
In my family, I have found disputes among family members about the ancestry of particular ancestors.

 

[Vanadium 50]

I would imagine

Have any data? First, rural counties are small, so if you restrict "southern white Amerricans" to rural residences, you're definitely talking about a small fraction of the population. For example, half of the NC population lives in counties larger than Johnston County, seat Smithfield, which is 10% Hispanic, compared to 17% nationwide. That seems reasonably indicative that people not descended from the original UK settlers (or descended from African slaves) have been moving in.

And since Smithfield > 10000 people, it fails even the loosest definition of rural. (No city nearby with more than 10K, 5K or 2.5K people)

The median county in terms of population is Columbus County, seat Whiteville. Officially rural (10K, but not 5K). But this point, the number of Asians, Hispanics, Pacific Islanders, etc. is quite low - but only 1/7 of the state lives in counties no more populous. Further, Whiteville is less than 50 miles from Wilminton, Fayetteville and Myrtle Beach.

The kinds of places you are thinking of are rare and getting rarer.

 

[Janus]

I've done some genealogy, and got my mother hooked on it. The way it generally works is that you take your family name (your fathers' last name) and your mother's maiden name (your grandfather's last name) and trace just those names back as far as you can take them. The rest of the people in the tree don't have a name you recognize, so you tend to ignore them. This makes for a very incomplete/biased view of your lineage.

Though this methodology can cause you to miss some interesting info. In my own case, I knew my grandparents all immigrated from Finland. But by tracing back through my Mom's mother's side back a few generations, I found a bit of German nobility. In the late 16th century, an ancestor of mine, a German military officer from a noble family, went North to Sweden and got involved in the present war between Sweden and Russia. He ended up with land near St. Petersburg, which was under Swedish control at the time. After a couple of more generations, Russia reclaimed the territory, and the family moved to Finland, and some generations later married into my maternal grandmother's line.

If I just kept to to Dad and Mom's paternal lines, I'd just find a long line of farmers for the most part.

 

[BWV]

Finding nobility that far back is just a bias as everyone has thousands of 16th century ancestors (15 generations with no inbreeding is 33K G^15 parents). Those ancestors who had high social status are more likely to have surviving records than our ancestors who scrubbed latrines

 

[Janus]

Finding nobility that far back is just a bias as everyone has thousands of 16th century ancestors (15 generations with no inbreeding is 33K G^15 parents). Those ancestors who had high social status are more likely to have surviving records than our ancestors who scrubbed latrines

In my case, while this particular family left Germany in the late 1500's, apparently they were not the only such family to do so. Up until 5 generations ago , they were still intermarrying with other German families, even while in Finland. It turns out that I have several branches that all came from different parts of Northern Germany which went North all around the same time. What intrigued me was what could have caused this exodus.
The best I can figure is that this occurred during the Protestant Reformation. At the time, much of Northern Germany had turned Protestant, while Southern Germany remained Catholic. There was much tension in the country (The Cologne War was one result). My guess is that a number of families, which had the resources to do so, moved North into Sweden to escape this, then eventually many of them ended up in Finland.

It was more of the historical context that interested me than any nobility part. And as I said, if I had stuck to just linear family names, I would have never known about having any German roots at all or this part of my family history, as those lines never leave Finland as far back as the 16th century. ( In fact, this particular branch is the only one I've found that extends outside of Finland so far.)

As far as inbreeding goes, I haven't yet found any direct evidence in terms of overlap, but I'm sure it has occurred. In most of the lines I have been able to trace, there isn't much movement, with generations all born in the same place, so the chances are good. On my maternal line I have three generations in a row (son, father, and Grandfather who all married wives with the same surname. ( though again, with Finnish naming traditions, this may mean nothing.)

I'm pretty sure that if I were able to find all those 15th generation ancestors, I would find significantly fewer distinct individuals than 33,000.

 

[BWV]

Likely the 30 Years War. Also Finland, Pomerania and some other areas of N Germany were Swedish possessions in the 17th century, so not too surprising that immigration would occur

 

[Janus]

Likely the 30 Years War. Also Finland, Pomerania and some other areas of N Germany were Swedish possessions in the 17th century, so not too surprising that immigration would occur

For the most part, the info is sketchy. You find birth and death dates and places, their children's birth dates and places, and you kind of try to form a picture from that.
I only lucked out with the one family line when I found a Swedish wiki entry on them which turned out to be treasure trove of info. All kinds of little tidbits beyond the usual stuff you can find. For example, my 6th great-grandfather, Gustav, served in the military from 1697 to 1734, retiring as a Lt. Colonel and died in 1742 in the Aland sea while escaping the Russians.
One of his brothers participated in the Battle of Oresund in 1658.
Gustav's son, Carl Reinhold, rose to the rank of Major in the Pori regiment. He was a "Naturalized Swedish Nobleman", introduced in 1776.
His daughter Catharina, in turn, was my 4th great-grandmother. She married a Major. ( A lot of marriages between military families in this line).

 

[mathwonk]

Genealogy can be fun, especially since as noted one has so many ancestors one can pick and choose quite widely which ones to mention. My mom, who died some time ago at over 100, pursued the study of those ancestors sharing her mother's maiden name for most of her life, even writing a book on it. "Our" ancestor of that surname arrived in the US about 1748, but the more distant ones can be traced, with less precision of course, back to a Scottish Baron, once banished by Macbeth, but later present at the coronation of Malcolm III, King of Scotland, in 1057. One descendant of this line perished fighting on the side of William Wallace at Falkirk in 1298, while other more recent ones were ambushed in Mexico while stealing cattle. In reference to the colonial period, ancestors on both mother's and father's side served in the American revolution, although not all that service is recorded in federal pension records.

The present interesting thread has made me aware how small a fraction of my heritage this lineage represents, and hence how inaccurate it is for me to say my ancestors came from Scotland. Moreover, although considered "white southerners", we have ancestors from Massachusetts, and likely also ones of Cherokee and possibly African American heritage. And that's just me; as you point out, our kids now have another equally large set of ancestors on my wife's side, seemingly almost entirely disjoint from these. Thanks for stretching my imagination. Until you stimulated it, I had little interest in my ancestors, since I felt their crimes are not my fault, and their successes do not reflect credit on me either.

 

[snorkack]

Finding nobility that far back is just a bias as everyone has thousands of 16th century ancestors (15 generations with no inbreeding is 33K G^15 parents). Those ancestors who had high social status are more likely to have surviving records than our ancestors who scrubbed latrines

What is the largest complete and distinct set of ancestors anyone has, at all? 15 generations with no repeats is 32 768, sure, and there certainly were far more than 32 768 people in the world but does anyone actually have all 32 768 distinct?

How many people actually do NOT have thousands of 16th century ancestors for the reason that their 32 768 ancestors are under 1000 distinct persons?

In my case, while this particular family left Germany in the late 1500's, apparently they were not the only such family to do so. Up until 5 generations ago , they were still intermarrying with other German families, even while in Finland. It turns out that I have several branches that all came from different parts of Northern Germany which went North all around the same time. What intrigued me was what could have caused this exodus.
The best I can figure is that this occurred during the Protestant Reformation. At the time, much of Northern Germany had turned Protestant, while Southern Germany remained Catholic. There was much tension in the country (The Cologne War was one result). My guess is that a number of families, which had the resources to do so, moved North into Sweden to escape this, then eventually many of them ended up in Finland.

My guess is a bit different. Pull rather than push.
16th and 17th century Sweden was trying to build up a modern state. The native nobles were few in number and unskilled in the advanced technologies of warfare and administration. For that reason, 16th and 17th century Sweden/Finland welcomed skilled immigrants of suitable cultural background - which meant Lutheran Northern Germany, upper classes (nobles, urban merchants, professionals and artisans). Peasants and urban common labourers were not welcomed because unskilled labour was found in Sweden and Finland locally.

 

[Janus]

What is the largest complete and distinct set of ancestors anyone has, at all? 15 generations with no repeats is 32 768, sure, and there certainly were far more than 32 768 people in the world but does anyone actually have all 32 768 distinct?

How many people actually do NOT have thousands of 16th century ancestors for the reason that their 32 768 ancestors are under 1000 distinct persons?
My guess is a bit different. Pull rather than push.
16th and 17th century Sweden was trying to build up a modern state. The native nobles were few in number and unskilled in the advanced technologies of warfare and administration. For that reason, 16th and 17th century Sweden/Finland welcomed skilled immigrants of suitable cultural background - which meant Lutheran Northern Germany, upper classes (nobles, urban merchants, professionals and artisans). Peasants and urban common labourers were not welcomed because unskilled labour was found in Sweden and Finland locally.

The more I dig into that Wiki page, The more it seems that it was the "warfare" part that drew them in. It extends beyond just this one direct line. Time and time again, I'll come across an entry with an ancestor who is a military officer marrying the daughter of another officer. Some of these had links leading to the other family,* which allowed me to expand the search.

Besides more in depth information, It provided independent verification of the tree I already had.

*This is actually a recent thing. The last time I referenced this page, it had only limited info on one family name. It has expanded significantly.

 

[mhe94626]

I am a descendant of English, Scotch-Irish, German and Swiss German "English Colonists" from the Mayflower to the Revolutionary War. I only had two ancestors who immigrated to the United States after the Revolutionary war; Both migrated to the US prior to the late 19th century. I don't know too many Americans who have ancestry that far back except some with Indigenous American ancestry. English colonies became the United States of America around 1791. This is not counting the French and Spanish Colonists that arrived before and during that time. France lost territories around 1801 what is currently known as the east of the Mississippi River and west of the Appalachian mts. New Spain-Mexico is basically west of the Mississippi River. The other reason this question is difficult to answer is because contrary to what may learned or read many Colonists arrived in other parts of the eastern united states in boats after and even before the Mayflower. Not all of them were English. Pennsylvania and New York had a diverse set of Northwest Europeans who settled states like New York, Pennsylvania. And there were Spanish colonists in South Carolina in George before Jamestown was settled in Virginia. Many Americans have some Colonial ancestry because some of their Ancestors came in ports like Ellis Island and San Francisco during the late 19th century - early 20th century and on planes after that. Good luck finding the answer. My ancestors came to the US for a variety reasons. Religious persecution, politcial reasons (some were colonists in North Ireland and were fighting Irish Catholics), economic reasons (some were able to get inexpensive land after the native americans died or lost territory.

There are only 2 ways to figure out the answer. Ask Americans if they have ancestors who lived in the Continental US prior to 1791 or find the number of people who were European Colonists who lived in the Continental US before 1791 and computer generate how many descendants currently live in the US.

 

[Hornbein]

I realize it is exponentially more, but I like the basic point of the Guardian article that every living European (and therefore white American) is a direct descendant of Charlemagne -- and essentially everyone else who lived and had children Europe in the 9th century.

I am skeptical of such claims, particularly if they come from a for-profit company. They are biased toward drama.

 

[Hornbein]

At risk of turning political on Martin Luther King day (still in some time zones...), cultural identity isn't supposed to be important anymore. It's interesting for personal reasons, but not terribly relevant in the grand scheme of things unless you are an anthropologist or... nevermind.

20th century thinking, this.

 

[Astronuc]

Part of the reason I'm curious about this is because the United States is often described as a "land of immigrants", but if one's roots in the country date back before the massive immigration waves in American history (during the 19th and 20th centuries), they may not consider themselves to be descended from immigrants (whether that is accurate or not).

If they have European, or even African, ancestry, they are descendants of immigrants. BTW, immigration was more or less continuous from Europe and Africa (forced in most cases) from the 1600s on.

I'm curious about the OP question. Why not ask if "What % of Americans have colonial roots?"

Forty-five of the 102 Mayflower passengers died in the winter of 1620–21! My wife is related to five passengers on the Mayflower: John Alden and Priscilla Mullins (married 1621, both 8th great grandparents), Priscilla's parents (William & Alice Mullins, who are 9th great grandparents), and John Soule (10th great grandfather). William & Alice Mullins, and Priscilla's brother Joseph Mullins, died in February 1621.

John Soule married Mary Beckett (or Buckett) who arrived on the Alice and Little James in 1623. Apparently, some of the immigrants from the Alice and Little James were sent back to England after they were deemed unsuitable for the environment. We do find some records to be inconsistent.
https://en.wikipedia.org/wiki/List_of_Mayflower_passengers_who_died_in_the_winter_of_1620–21
http://mayflowerhistory.com/mayflower-genealogy

Most of my wife's ancestors are English and French Canadian and Dutch (father's side) and Irish, England, Germanic Eu (mother's side). She related to the first governor of Rhode Island and some of the early presidents.

I'm a more recent immigrant (mid 20th century). My ancestry is mostly Scottish, English, Germanic Eu, Norway, Wales, Ireland, Sweden/Denmark, although a different genetic testing company put me more Scottish/Irish/Welsh/Scandanavian/Finnish/Aegean (Greek and S Italian) and Ashkenazi Jewish. Go figure.

Although I wasn't born in the US, the majority of my existing relatives live (and were born) in the US, followed by England/Scotland/Wales, Australia, Canada, NZ, Ireland, Sweden, Netherlands, Germany, France, . . . . I've also identified relatives who have African and Indigenous (North and South America, Australia, NZ, Pacific Islander), and some with a combination aforementioned groups. Some US relatives go back to 1600s, some 1700s (New England or Virginia), some during the 1800s, and a few more recently in the 1900s. Some relatives moved from US to EU countries, where they died.

Many of my ancestors were farmers, miners or labourers, some were merchants, and back in the 1500s-1600s, some had estates, which were lost during the English Civil War. One of my paternal ancestors was an Archbishop of Canterbury, which tickled my father (clergyman) and would have tickled my paternal grandfather (clergyman) had we known before he passed 20 years ago. Along the way, I've found relatives who died in WWI, WWII, Korean War, and others. I have a 3rd great grandfather who died/disappeared at sea near Sulawesi Tengah, Indonesia in 1841; I don't have the details.

 

[snorkack]

Hi everyone. One of my pet hobbies/interests is in history, and I've done some background reading on early American and Canadian history, including the history of immigration to the US.

One of the questions that I have is what percentage of white Americans are descended from those Europeans who arrived during the colonial period (i.e. prior to the US gaining independence in 1776, so primarily during the 17th and 18th centuries), and those who arrived in later immigration waves (the 3 waves documented are the first half of the 19th century, the period between 1880s to 1920, and the post-World War II period).

I tried to do a Google search, but I haven't found any source or reference identifying what it is. My own suspicion is that a vast number of white Americans descend from later waves of immigrants and that only a minority descend from the early colonial period (although this may well differ depending on what state one lives in). Any thoughts?

Do you count proportion of people descended from colonial stock, or proportion of people with some solonial ancestry?
For the first, there WAS an answer in 1920. Not a reliable answer, there are a plenty of methodological issues with the estimate, but it was the law of the land for over 40 years.
https://en.wikipedia.org/wiki/National_Origins_Formula

The formula required classification of the national origins by birth or ancestry of all White Americans, except those having origins in the nonquota countries of the Western Hemisphere. The total White American population in 1920 was estimated at 94,820,915. Whites with origins in the Western Hemisphere were estimated at 5,314,357

This left the total relevant population for the quota calculation formula at 89,506,558.

49,182,158 were deemed to be of immigrant stock, accounting for 55% of the total

45.0% of the total: 40,324,400 descendants of colonial stock

So, in 1920 census, 40,3 million of 94,8 million whites were counted as proportional descendants of the 3,2 million whites present in 1790.
How many whites present in USA in 2020 are (proportionally) descendants of those present in 1920? Remember that immigration to USA was largely restricted between 1920 and 1965, and largely nonwhite since 1965.

 

[Janus]

My ancestry is mostly Scottish, English, Germanic Eu, Norway, Wales, Ireland, Sweden/Denmark, although a different genetic testing company put me more Scottish/Irish/Welsh/Scandanavian/Finnish/Aegean (Greek and S Italian) and Ashkenazi Jewish. Go

The Finnish may come from "Forest Finns", who were a group that had settled in Sweden. Forest Finn were included among early Swedish settlers to America, and are credited with popularizing the log cabin in the colonies.

 

[BWV]

Do you count proportion of people descended from colonial stock, or proportion of people with some solonial ancestry?
For the first, there WAS an answer in 1920. Not a reliable answer, there are a plenty of methodological issues with the estimate, but it was the law of the land for over 40 years.
https://en.wikipedia.org/wiki/National_Origins_Formula

So, in 1920 census, 40,3 million of 94,8 million whites were counted as proportional descendants of the 3,2 million whites present in 1790.
How many whites present in USA in 2020 are (proportionally) descendants of those present in 1920? Remember that immigration to USA was largely restricted between 1920 and 1965, and largely nonwhite since 1965.

So to attempt some bad math, if its 4 generations from the 1920s to a middle aged white American today, and assuming only 'white' great-grandparents (who qualified as 'white' in 1920? did Italians or Jews?) they have a roughly a (1-0.4)^8 or ~1.7% chance of having a grandparent with no colonial roots

Vastly oversimplified due to culture, class, geography, religion etc

 

[Hornbein]

Cultures usually don't mix much. I live in Bali, which was invaded in 1347 or so. There is still not much mixing of the two cultures. They have separate languages. Similarly in India with Hindus and Muslims.

 

[snorkack]

So to attempt some bad math, if its 4 generations from the 1920s to a middle aged white American today, and assuming only 'white' great-grandparents (who qualified as 'white' in 1920? did Italians or Jews?)

Italians plainly did. "Italy" is listed in National Origins Formula, at 3,65% - none of them colonial.
Jews counted as "white", too, under the country they came from.

they have a roughly a (1-0.4)^8 or ~1.7% chance of having a grandparent with no colonial roots

Vastly oversimplified due to culture, class, geography, religion etc

Yes. Starting with what that 0.4 meant.
US whites of 1920 included 12.1 million immigrants. There clearly had no colonial roots (almost all of them - excluding the probably tiny number of European descendants of people who had returned from America).
But then the formula estimates 17.6 million "children of immigrants". And that´s not actual immigrants. It is a representative fractional number. It might mean 17.6 million people who were US born children of two immigrant parents. Or it might mean 35.2 million people who were children of one immigrant parent and one US born parent. Or any combination of people of these two types.
Perhaps that information was also collected somewhere, but it was not included in National Origins formula.
There is a nice example of a living American with no colonial roots, but not US American. Pope Francis. Born in 1936. Father an immigrant - immigrated in 1929. Mother born in America in 1911... to two parents who were both immigrants. So no colonial roots.

The easier exercise to find the rough percentage is then to look at the white Americans who do NOT have colonial roots - either recent (20th century) immigrants, or descendants of immigrants who married other immigrants.

 

[StatGuy2000]

Do you count proportion of people descended from colonial stock, or proportion of people with some solonial ancestry?
For the first, there WAS an answer in 1920. Not a reliable answer, there are a plenty of methodological issues with the estimate, but it was the law of the land for over 40 years.
https://en.wikipedia.org/wiki/National_Origins_Formula

So, in 1920 census, 40,3 million of 94,8 million whites were counted as proportional descendants of the 3,2 million whites present in 1790.
How many whites present in USA in 2020 are (proportionally) descendants of those present in 1920? Remember that immigration to USA was largely restricted between 1920 and 1965, and largely nonwhite since 1965.

Immigration to the USA was only severely restricted between 1920 and 1965 to those who were not of British, Irish, or German ancestry. See the following on the Immigration Act of 1924.

https://en.wikipedia.org/wiki/Immigration_Act_of_1924#Quota_calculation_formula

As per the Immigration Act of 1924, a quota system had been set up based on nationality of people's origins based on the 1890 census. Since people of British, Irish, or German origin made up the vast majority of people in the US at that time, people from these areas were given considerable latitude to immigrate to the US, while essentially restricting or banning immigrants from all other regions.

 

[snorkack]

Immigration to the USA was only severely restricted between 1920 and 1965 to those who were not of British, Irish, or German ancestry. See the following on the Immigration Act of 1924.

https://en.wikipedia.org/wiki/Immigration_Act_of_1924#Quota_calculation_formula

As per the Immigration Act of 1924, a quote system had been set up based on nationality of people's origins based on the 1890 census. Since people of British, Irish, or German origin made up the vast majority of people in the US at that time, people from these areas were given considerable latitude to immigrate to the US, while essentially restricting or banning immigrants from all other regions.

My point is that the number of immigrants in 1925-1965 was small compared to the numbers 1900-1914. So summing up their numbers would be relatively easy.