How Many Generations Ago Was America Founded?

It’s fun to find ways to connect your family to historical events. One way to do that is by comparing time in generations instead of years. How many generations ago was America founded?

America was founded in 1776, which is between 7 and 10 generations ago (depending on the definition of generation used). A family’s actual number of a family’s generations since that time may differ from this average range of generations. Here is what you need to know about calculating generations.

Ready to see how to figure out how many generations ago America was founded? Keep reading – and we’ll show you how to calculate that and how to figure out how many generations since other important events, too!

America Was Founded in 1776

The first thing we need to know is when the historical event happened. America declared its independence in 1776.

There’s a lot more to it than this, but let’s keep today’s history lesson simple. The colonists declared themselves free from King George III’s rule after a series of events that left them feeling frustrated, underrepresented, and unfairly treated. After realizing that the situation wouldn’t change without drastic measures, they decided to form a new country of their own – so that they could have the representation and chance to impact their country’s laws, taxes, and tariffs.

Technically, our current form of government wasn’t formed until later – specifically when the Constitution was signed and adopted in 1787. However, we still celebrate America’s birthday based on when we declared independence from Britain’s rule on July 4, 1776.

So let’s do some math to figure out how many years old America is.

2020 – 1776 = 244

So in 2020, America will be 244 years old. Now let’s figure out how long a generation is – so we can see how many generations ago America’s founding took place.

How Many Years Long is a Generation?

A generation can be anywhere between 10 and 50 years long, depending on which definition you use. So let’s start by defining a generation – because there are several definitions. According to both the Cambridge and Merriam-Webster dictionaries, a generation is defined thusly.

Gen-er-a-tion (noun)

1. all of the people (of about the same age) born and living within a society or within a particular family

2. a period of about 25 to 30 years, in which most human babies grow to adulthood and have their own children

3. a body of living beings constituting a single step in the line of descent from an ancestor

4. the average span of time between the birth of parents and that of their offspring

Definitions pulled from both the Cambridge Dictionary and the Merriam-Webster Dictionary.

The first definition is a social definition – like when we call an age group by a particular name (like “Millenials” or “Baby Boomers”). Those retroactively-created labels and names have been given to generations for decades.

The second through fourth definitions, though, is what we wanted. They’re more applicable to genealogists and our quest to figure out how many generations since America’s founding.

So the average span of a generation, per two dictionaries, is between 25 and 30 years, or 4 generations per 100 years.

However, before we celebrate having found our answer, let’s see what scientists and genealogists say about how long a generation is. The International Society of Genetic Genealogy’s (ISOGG) Wiki page on genealogy length (click here to read it) says that a generation can be 15, 20, 25, 30, or even 35 years long. They also point out that there are known parents as young as 12 or younger – which means a generation might be even shorter than 15 years in some instances.

So if we want to see how long each individual generation is, we have to average the ages of each parent at the birth of their children.

  • For example, if you had 4 kids at the ages of 24, 26, 28, and 30, then your kids’ average generation is 27 years (or (24+26+28+30)/4).
  • Or if you look back in your genealogy and note your maternal lineage’s ages when children were born to average a generation length. For example, let’s say your mother was 27 when she had you, your grandmother was 26, your great-grandmother was 18, and your great-great-grandmother was 26. Your maternal line’s average generation would be just over 24 years long.
  • You could also average the ages of fathers across generations to determine an average paternal lineage generation.

However, the ISOGG also admits that this can be a long and cumbersome way to figure out how long generations are. Too much research to figure out those ages and dates – and there has to be an easier way to do it with averages that are more reliable.

Thankfully, Donn Devine found a statistical average based on measuring a whole lot of DNA data and reading lots of research. You can read his article on the ISOGG Wiki. In any case, he uses DNA data to determine that a generation has more than 25 years to it – and that it’s different for paternal and maternal lines.

  • He found that paternal or male generations tend to be 33 years long – or that there are 3 generations per 100 years for me.
  • Devine found that maternal or female lines tend to be 29 years long, or about 3.5 generations per 100 years.

Those different numbers make a huge difference in determining how long it’s been since an ancestor lived – or since an important historical event occurred. So having these different numbers can radically skew how our perception of how long ago events happened.

Even so, if you’d like to have a more-specific DNA-based answer on how many generations back your ancestors are, go get a DNA test done. If you don’t know which DNA test to get, check our recommended DNA tests for genealogical purposes.

So how many years long is a generation? Again, it can be between 10 and 50 years, depending on the definition we want to use. However, for ease of calculations, let’s consider that most generations will fall somewhere in the following ranges.

  • a 25-year generation
  • a 30-year generation
  • a 33-year (male) generation
  • a 29-year (female) generation

Remember – these numbers are based on general averages and DNA-based data.

So next, let’s get back to our original question of how many generations ago America was founded – and how many generations back other important historical events were. But because we now know that a generation isn’t a number that’s set in stone, let’s calculate the answer using multiple numbers. That way, we get a range – but it’ll be far more accurate than if we only used a single definition’s value.

How Many Generations Are There in American History?

Each historical event will have a different answer – that’s expected. The September 11th terror attacks were far more recent than the founding of Jamestown colony (back in 1607). So it’s only logical that there are fewer generations since 9/11 than Jamestown.

But let’s still answer the question – and we’re going to calculate the answers based on our four common lengths of a generation. Just to remind you, this is what they are.

  • a 25-year generation
  • a 30-year generation
  • a 29-year (female) generation
  • a 33-year (male) generation

The order is slightly different than it was above – because we’re going to list them in this order. That way, you’ll be able to see the total ranges easier.

Now, here’s how we calculate each number for each generational number as listed above. Don’t forget to use the order of operations. So we’ll subtract the years first and then divide by the generational number.

(Today’s Year – Historical Event’s Year) / Generation

So for example, America’s Founding will be calculated four ways.

  • (2020-1776)/25 = 9.76
  • (2020-1776)/30 = 8.13
  • (2020-1776)/29 = 8.41
  • (2020-1776)/33 = 7.39

Using those numbers, we can see that America was first founded an average of 7.3 to 9.76 generations ago. However, for ease of use, let’s use a statistical significance to round those values and say that America was founded between 7 and 10 generations ago. That’s how we got our answer!

But let’s look at some other important dates in American history – and see how they fit into the generational timeline.

Generations Back to Important Historical Events

Event and Year25-year Generation30-year Generation29-year Generation (Female33-year Generation (Male)
Columbus discovers America in 149221.1217.618.216
Colony of Jamestown founded in 160716.5213.7614.2412.51
The Pilgrims land at Plymouth Rock in 16201613.313.7912.12
Signing of the US Declaration of Independence in 17769.768.138.417.39
The U.S. Constitution signed in 17879.327.768.037.06
The Louisiana Purchase is made in 1803 8.687.237.486.57
The Civil War begins in 18616.365.35.484.81
World War I begins in 19144.243.533.653.21
U.S. enters World War II in 1941 3.162.632.722.39
The Korean War begins in 19502.82.332.412.12
The Vietnam War begins in 19552.
Civil Rights “I Have a Dream Speech” given in 19632.281.91.961.73
First man to walk on the moon in 19692.
The fall of the Berlin Wall in 19891.
Terror attacks in New York City in 20010.760.630.670.57

Pretty cool, huh? It’s crazy to think of some of these events as so far away – when you then realize that the first man to walk on the moon wasn’t actually that far away – it was only an average of 2 generations back!

Related Questions

How Many Generations Does it Take to Be Considered an American? From a legal standpoint, an American is anyone with citizenship, whether through birth, naturalization, or adoptive legal processes. Immigrants may be considered Americans from the first or second generation, depending on individual circumstances and preferences.

How Many Generations Have There Been Since Columbus? Columbus reached the Americas between 16 and 21 generations ago, depending on which generational average number you use. For specific calculations, please refer to the table in this article.

How Many Generations Ago was 1800? 1800 was between 6.7 and 8.8 generations ago, depending on which generational average you use. Please refer to the table in this article to see how many generations it has been since other important dates in history.


  • Devine, Donn. “International Society of Genetic Genealogy Wiki ISOGG Wiki.” How Long Is a Generation? Science Provides an Answer – ISOGG Wiki,
  • “GENERATION: Definition in the Cambridge English Dictionary.” GENERATION | Definition in the Cambridge English Dictionary,
  • “International Society of Genetic Genealogy Wiki ISOGG Wiki.” Generation Length – ISOGG Wiki,
  • Rosenberg, Matt. “What Is the Official Name for Every Generation?” ThoughtCo, ThoughtCo, 12 Feb. 2020,


I'm a ginger who loves reading, eating, being a nurse, doing genealogy, spending time with my family, and writing about it all. I believe humor is the best medicine, followed very closely by chocolate and tacos. To read more about me, click here.

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