For all the talk about the origins of role-playing little time is spent on the actual catalyst-the wargame.
Most people tend to envision large amounts of space time and money building up armies to battle. But wargaming is scalable in either direction.
So for someone who would like a taste I offer the following:
Battle For Moscow
http://grognard.com/bfm/index.html
This is a great little free game to try out.
The intro is brief and informative
http://grognard.com/bfm/intro.html
And if you find the basic game to your liking they have included extra rules you can print for a longer game.