But there's more to the story.
Darrow's design was strikingly similar to one patented on January 5, 1904, by Lizzie J. Magie, a Quaker woman from Virginia. He game was called The Landlord's Game and was based on the philosophy that the renting of land and real estate produced an unearned increase in land values that profited a few individuals (landlords) rather than the majority of the people (tenants).
You can read more about Monopoly's origins in this article written by About.com's Guide to Inventors, Mary Bellis.
More about the history of Monopoly is also available on this site.