How did Canadian and U.S. accents come to sound so similar?

I was wrong. It lasted for a few minutes. Sorry Jamie there are MANY accents in Canada and the United States. Just like in England because London is the main city not everyone speaks with a cockney accent.You obviously have no education in linguistics and how a language or accent develops. When you speak of the English accent do you mean Midlands , Yorkshire. , or plain old Cockney. What does the Queen have to do with this.

We do sound alike, but most Americans can pick a Canadian out pretty quickly and vice versa. We sound similar because of proximity to each other.

First things first: Canada was French from 1534 till 1759, and British from 1759 till 1867. By rights, we all ought to have French accents. Not British ones. Second things second: Both technically and legally, we didn't maintain Britain's Queen as sovereign. The British made some radical changes to the monarchy when they gave up their Empire. The simplest way to explain it is with an analogy: -Any nation that wants it can have UN representation. -All UN nations are separate, equal & independent of and to each other. But the United Nations isn't considered American for being based in New York. Nor is any UN nation considered as 'keeping ties to the US' by being a UN member. Like the UN, the monarchy's multinational & not tied to a single country or government. Last things last: The "standard accent" in Canada is similar to the US equivalent. But there are significant regional differences. Nobody's going to mistake a US Southerner for a Canadian and vice-versa. Same as nobody's going to confuse a Canadian Newfoundlander with any American: Link - http://www.youtube.com/watch?v=pQc43b4OsRg Link - http://www.youtube.com/watch?v=zqLuIXwsLDw&feature=fvwp&NR=1

Canada and the US were settled in similar time frames by people who came from similar places, and there has been a lot of coming and going between the two countries over the last couple of centuries. Two of my grandparents were from the US originally. The surprise would be if there was no similarity of accents in the two countries, but there are some American accents so different from the average Canadian one that I have trouble understanding them when I hear them on TV. Because Canada was under British rule for longer didn't necessarily mean that Canadians during that time heard more British speech, so I don't know why Canada would be expected to sound much more British. Until there was radio, the average Canadian wouldn't have heard any British speech at all except from people who had come from Britain. The US had some of those too.

Just because Canada was a British colony for longer than the USA, it does not mean that it should have more British accent. I can only assume that the USA and Canada's accents sound so similar is because they both originated from the original British and through a sort of isolation on this side of the Atlantic, the accents evolved into what we know them as today. In addition, some historians argue that the British accent we know today was not the British accent of the colonial era. So perhaps the accent we hear in Canada and the USA today is the original British accent of the 1700s. Just speculation.

Both Canadians and Americans are originally English. Maybe the English who invaded these countries were from the same part of England.