So what is Canadian whiskey? Well, it's whiskey made in Canada. Generally speaking, Canadian whiskey is, people think, Crown Royal, and that's really where it stops. Canadian whiskey was very popular during Prohibition, because it was legal to make in Canada, and then you could just sort of make sure it got across the border in the middle of the night.
It tends to have a higher rye content, because rye is a very hardy grain that grows well in cold climates and with people who say "Aye" a lot. You have rye whiskeys, and you can also do more artisanal, smaller productions with higher wheat contents, depending on what you can source.
It's not very much different from American whiskey, except that American whiskey has a wider variety of styles, has some illegal history, and has more people making it. While it has a fairly long, if undistinguished history, much like Canada itself, it's a delicious, light, easy sipper, and, Lord knows, if you want to tip one back to Dimebag and have a sip of Crown, you do that. It's whiskey made in Canada. It's not bad. At least they do that right.