I understand that Canada was far less developed than the 13 Colonies as of the 1770's, and that the American Revolution led to a massive influx of United Empire Loyalists into what's now Canada. However, there were already quite a few English (and historically-French) communities under British control which didn't become part of the USA.

To what extent did the rebellion reach the now-Canadian parts of British North America? Did the inhabitants completely decline to join the revolution? If so, what factors caused these communities to react differently from the ones that rebelled?

Edit: Asking out of curiosity. I'm a Canadian with no North American ancestry reaching that far back, living in an area near the border in which there was a lot of Loyalist immigration.