George S. Parker, the original Parker Brother, was always interested in the financial industry. His first game was called Banking and was developed as a pass-time between his friends and family. Players had lettered cars and would speculate on how long it would take for another similar card to appear. The object of the game was to amass as much money by winning the speculations. In order to grow there was the concept of a "bank" that would issue cards with interest. It was also possible to form partnerships and engage in profit-sharing. It was the first game he would publish, on his own, and he made about $1,500 for his troubles in today's dollars. The influence on Monopoly can't be ignored, especially when a global version of Monopoly is about to be introduced with Google Maps and Dr. Danger has some ideas.
You can read more about the history of the Parker Brothers here and, of course, watch The Venture Brothers on Cartoon Network's Adult Swim.