When did Canadians get the "polite" moniker?

Because they mostly treat all people with respect and are willing to use the manners that they were taught.

In my experience, Canadians are extremely polite unless they're from Alberta. No idea what makes them so unpleasant.

Canada or Canadian people are nice. Their leader at the time is like Jim Jones from Gianna. He is an insult to logic.

One difference AMERICANS see is that Canadians seem much more polite than Americans.  If you were an American of average height, and you moved to Japan, you'd be considered tall.  Just by comparison.  So in Canada, among Canadians, a particular Canadian might be considered polite or not so much.  But when we Yanks go up there we're always impressed with their average level of politeness.

No.  It was before the internet.  I traveled to Canada before the internet was a thing, and people told me to expect them to be polite.  And they were right.

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