Mountains are not bigger in Canada than the US and horseback riding are equally popular in the rural areas of the great plains regions of Canada and the US. The reason they choose Canada over the US is because Canada and Britain have long standing allies, where as the US separated violently from Britian, although they are allies now. Britain has a military training facility in one of the most sparsely populated areas of Alberta.
Soldiers have been training on a large scale there since the 70s. It's open expanse of space, proximity to the Canadian Rocky mountains and decent climate is a good reason they chose this area.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.