For what it's worth, I've read several explanations for the left/front association in North America. One is that it arises from the misplaced fear that a right-handed rider would squeeze the brake too hard and flip over the handlebars. Sheldon Brown opined that it was so that the rider could use a hand to signal while using the primary brake, but that doesn't make sense since in the US, where you ride/drive on the right, one usually uses the left arm to signal.

I leave my bikes set up with left/front because I'm left-handed and I prefer to have my stronger, dominant hand control the more important brake.