When was the original Monopoly board game created?

Lizzy Magie invented the original Monopoly game in 1903 and called it the Landlord's Game. She invented the game as a tool for teaching about economic inequality.

Lizzy Magie invented two distinctive set of rules for the game: an anti-monopolist set in which every player earned rewards for wealth creation and a monopolist set in which the ultimate goal was to crush the opponents. Although she intended the two contrary set of rules as a way to prove that the first set of rules were morally superior, the monopolist rules caught on. Parker Brothers bought the rights to the game in 1935 and changed the name to Monopoly.