参考：
But it was nothing like so simple, the rebellious nation was not a nation, but a string of separate colonies clinging to a coastline. We tend to think of them as the only white inhabitants of the continent. But if in the 1750s you'd gone over the mountains into the interior, you would have come up against the French and the root cause of the War of Independence.

From Maine to the Ohio River, the French had built a whole chain of forts, intending once for all to hem in the English colonies and maybe to conquer the rest of the hinterland. This one is Fort Ticonderoga on Lake Champlain in Upstate New York. The day came when the French drove east into the fringes of the English colonies. And Virginia sent out a young soldier in his twenties to stop them, at what is now, Pittsburgh. His name was George Washington. He failed, and retreated. The next year, a much larger force under General Braddock literally had to hack a road through several hundred miles of the wilderness to the same fort at Pittsburgh, and he also was beaten. So the British sent over a large expeditionary force to come to the rescue. They eventually won, but only after nine years. They suffered atrociously in the woods and plains out there both from the French and their Indian allies and in pitched battles in such places as this.

They had a few battles here, didn't they?
Yeah.
Benedict Arnold. Oh, yeah, but he was a baddie, wasn't he, in the end?
Yeah, he was the one. Note the bar sinister.
Where's the bar sinister?
How about that, the old cannon right down there?

The Black Watch Regiment had a brutal experience here. It had one of the worst losses in the history of the regiment, and this was in an engagement in which 15,000 British colonial troops were stood off by 3,500 Frenchmen who had the luck to be under command of General Montcalm. Now the battle lines out there, of course, are obliterated by now by time, growth, foliage, but we do have a rather grim personal relic of these wars which is a lead bullet chewed on by a British brigadier while he was having his leg sawn off, for it would be 100 years before anesthetics were introduced to the battlefield. And you can still see the indentations of his teeth on it. The operation was successful, but the patient, died of shock.

Well, at the end of this nine years' war, the American interior, from Canada all way south for a thousand miles was held, and the French lost America forever. We can only guess at the cost in blood, but in money, it cost the English taxpayer a fortune and the national debt was doubled. So, understandably, I think, the English began to feel that the colonies should do something for their own protection. Troops would have to be raised to patrol the greatly expanded western frontier, where the French and the Indians, though beaten, were still smarting. Now, strangely, this idea came as an awful shock to the colonies. They'd been on a very loose rein to the old country for a long time. And the young men who'd done the fighting expected to do what Americans have done ever since after a war, which is to disarm, demobilize, forget the whole business of war and get back to normal. But things weren't normal. There were few jobs and there was a general depression. And the ex-soldiers decided they'd like to pull up stakes and move on west. And sitting in their streets, and their alleys in the east, they must have thought back with much yearning to the lands they'd fought in, the new rich lands beyond the Appalachian Mountains.