This year's July 4 Independence Day celebration comes at an interesting time in the American story, when many of us are reassessing history and trying to see the Founding Fathers in context.

Part of that context is just how different life was in the colonies in 1776 compared to now. It's the old saw: Even the most unlikely things seem inevitable in retrospect.

Here are 10 facts about the new nation the Founding Fathers were building that demonstrate just how different it all was from ours today. I think they tell an inspiring story for anyone trying to take on a new challenge that seems impossible.

1. It was very small.

The entire population of the United States at the time was about 2.5 million people, well under 1 percent of what it is today, according to the U.S. Census. That's about the size of the metro area around San Antonio now, or else halfway between the populations of Kansas and New Mexico. 

2. It was only partially free.

A massive number of people were enslaved. The Census Bureau source above doesn't break it out, but estimates run as high as between 500,000 and 700,000 of the 2.5 million were enslaved at the time of the revolution. Of course, most women were not allowed to vote (except in New Jersey, but that's another story).

3. People died young.

Average life expectancy of a white male at the time was about  38 years, compared to about 78 now. Very high infant mortality back then affected this significantly. If white men like the Founders lived to age 60, odds were good they'd live to age 75; their average age at death turned out to be about 65.

4. Yet, they were healthier than you might think.

Medicine was nothing compared to today, but as a proxy for health, Americans were fairly tall, with men averaging about 5 feet 8 inches in 1776, just an inch shorter than today. The most common explanation is that nutrition was actually better for average Americans then.

5. The economy was very different.

You know of course that it was an agrarian economy, and the industrial and technological revolutions were far in the future. But as a result, almost everyone was an entrepreneur--including among the Founders. (However, there are two asterisks, in that many of them inherited immense wealth or were rich because of slavery.) Today, about 9 percent of Americans own a business.

6. Standards of living were high.

The combined U.S. economy was about 30 percent the size of Great Britain's. However, the U.S. standard of living among free people was considerably higher because of a smaller population. 

7. Families were big.

This is both related and predictable. Families were big, an average of 5.79 people, according to the first census in 1790. Today, it's about 3.14.

8. Taxes were low.

Surprising, right, given what we know about the Boston Tea Party? But the average effective total tax rates back then were between 1 and 1.5 percent total. At the same time, government services were very limited.

9. There were big sacrifices.

During the Revolutionary War, about 50,000 Americans were killed, wounded, or died from noncombat conditions (disease, accidents). Combined, this adds up to about 1 percent of the total population. The comparable rate for the Civil War was 2.1 percent (counting both sides). For World War II, it was .39 percent.

10. But there was a surprising advantage to limited technology.

The penalty for signing the Declaration of Independence was severe if the signatories were caught, or if the revolution had not succeeded. But the founders were protected by a practical consideration: Poor communication and travel in the 18th century would have made it very hard for the British even to find most of the signers, at least according to historian Denise Kiernan.