Lorindol

Here is a map showing where the majority of Russia's population lives:

https://maps-russia.com/maps-russia-geography/russia-population-density-map

The largest part of Russia is the vast Siberia, which is basically just endless forests, mountains and arctic tundra with few cities here and there - and the winters can be extreme. If not for the rich resources and the jobs that extraction of those resources creates, not many would choose to live there.

Yes. Casualties are soldiers who either die in battle or get wounded badly enough to be taken out of action for a longer time.

I had this book when I was a child.

The illustrations are permanently burned to my mind's eye.