Contrary to popular belief, Monopoly was not invented by Charles Darrow. In 1904, more than a quarter of a century before Darrow's game, U.S. Patent 748626 was awarded to Lizzie J. Magie for The Landlord's Game, which she devised as political propaganda for the theory that the rent market conferred monopolistic advantages on the landowner. The game quickly spread through the Quaker community under the name Monopoly, with many people adapting the rules and renaming the squares to local placenames.

In 1931 Charles Darrow was taught a variant of the Monopoly game, based on placenames in Atlantic City, by an acquaintance, one Charles E. Todd. By the end of 1935, Parker Brothers had sold hundreds of thousands of copies of a game Darrow claimed to have invented.

Darrow was not even the first to attempt to market the game commercially. After Monopoly became a gigantic success, Parker Brothers discovered and bought out not only Lizzie Magie's original patent but also "Finance" by Dan Layman and "Monopoly" by Luis Thun. (Dan Layman, ironically, had changed the name on legal advice that he could not trademark Monopoly since the game was already known in the community by that name.)

To preempt speculation, Parker Brothers subsequently moulded the story of Monopoly's invention into an American legend which they began to print on Monopoly boxes. The truth only came to light in the 1970s when Parker Brothers challenged Ralph Anspach's game Anti-Monopoly for infringement of trademark, provoking Dr. Anspach to investigate Parker Bros.' legal claim to the word.

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