- One of the earliest versions of Monopoly was invented by Elizabeth Maggie Phillips which she named "The Landlord's Game." She patented the game in 1904.
- In 1933, Charles Darrow learned and played one of the early versions of Monopoly. Another game called "Finance" was on the market in the early 30's in mid west. After copyrighting an improved version of the Landlord's game and changing the name to Monopoly, he then sold it in 1933 to Parker Brothers. Robert Barton of Parker Brothers also bought up the patent rights from Maggie-Philips and another game called "Finance" and settled claims involving two similar games. Monopoly went on to be Parker Brothers' biggest selling game of all time.
- In 1974 Dr. Ralph Anspach invented the Anti-monopoly game. Parker Brothers sued him for the use of their name, but he won in court after an 8 year fight.
- For more about the Parker Brothers, see this entry in the wiki.
- Vertical File in Salem Collection - Parker Brothers
- Vertical File in Salem Collection - Phillips, Elizabeth M. (Landlord's Game)
- Monopoly : the world's most famous game by Philip Orbanes
- The Monopoly Companion by Philip Orbanes
- The Monopoly Book : strategy and tactics of the world's most popular game by Maxine Brady, 1974.
- "Why Monopoly is more than just a game" Boston Sunday Globe, Nov. 4, 1990, p. A1