Eh, not really. I don't know that much about American history, but I kinda guessed that most of the characters were based on real people. All you need to know really is general knowledge about Abraham Lincoln, like him being honest and that he chopped down a tree, etc.
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Still the number one reason for the success of the Internet.
http://img.photobucket.com/albums/v192/FAH_Frenchie/YANsig02.jpg