Well, there are natural rivalries, like a close-to-the-chest commissioner who wants to control everything and the media who want to inform the public about what's going on...
There are the rivalries born in the intensity of a 6 or 7 game playoff series. Here's an example of one moment that created some strife between a couple of teams and fanbases...
And then there's just the rivalry surrounding bringing the Stanley Cup back to Canada...
