Charles B. Darrow, an unemployed salesman, sketched the prototype board game on a tablecloth at his home in the Germantown neighborhood of Philadelphia, using 21 street names from Atlantic City. (The final space, Marvin Gardens, was a name taken from the neighboring community of Margate City, where it is spelled Marvyn.)
The Parker Brothers game company rejected Mr. Darrow's proposal, so he went to a printer and began selling it himself. It caught on so quickly that Parker Brothers eventually reversed itself. It began mass-marketing Monopoly in 1935, and that year it became the world's best-selling board game.
Versions of Monopoly were played for decades when the game was taught to Darrow, according to the real history. He patented the game, robbed the creators of the credit and the game's publisher fought for 40 years to hide this fact.
Louis Thun, who played the game with the person who taught Darrow in 1931, said, "It wasn't at all clear to me how Mr. Darrow could be the inventor of a game ... we'd played since 1925."
Actually, this has been pretty well known for a long time, maybe it was just speculation prior to this though. Still a good read.
i was always told the game was invented by a man who was serving time in the atlantic city jail and he drew it on the wall.