Whenever I start writing a novel or short story I do a little bit of world-building. I usually start with a map and develop names for countries, major cities, bodies of water, and mountain ranges. Then I start plotting them on the map and take a look at what relations they could have with one another.
For example: does country A have a peaceful border with country B, or do they constantly war with one another? Does this river have an affect on this town or this economy?
Then I usually get into style of government, leaders, and brief histories that I can tie into my story.
How much world-building do you do before you write your novel? What types of questions do you ask yourself regarding world-building?