Since IW very nicely posted the manual on their site I just wanted add to Cal's comments by saying that a fun part of the manual is the section that gives background on the various nations and comments by one of the developers as to influences on nations or group of nations (note that unless the manual has been updated this won't include the nations that were added in patches after the initial release).
Valerius.
Valerius joined
This member has provided no bio about themself...