What If Nova Scotia had joined the Thirteen Colonies during the American Revolution?

Then why are Georgia and Maine not British? They were reconquered and held to the end of the war.

No they weren't. Georgia had been briefly overrun in 1779/80, but by the time of Yorktown it had been lost again, and only Savannah remained in British hands.

Similarly in Maine. Britain still held a seaport or two but not the country as a whole.

If NS signs up to the American cause, then it won't be willingly abandoned. Georgia and Maine are proof of that.

How do you "abandon" something you have never held?

There was no way NS could "sign up" to the American cause, any more than Bermuda or Jamaica could. It was separated from the 13 colonies by sea and by wilderness. In theory, I suppose, some Nova Scotians could have got together somewhere (well away from Halifax) and declared independence, but they'd have been captured or chased into exile within a week or two. If any NS delegates had turned up at the Continental Congress, it could have seated them if it liked, but they could not have returned to NS unless they wished to be arrested.

After all, the Americans never managed to conquer East Florida during the ARW, though it was more accessible than NS.
 
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