It is derived from The Landlord's Game, which was created by Elizabeth Magie
in the United States in 1903 as a way to demonstrate that an economy which rewards wealth creation is better than one in which monopolists work under few constraints.
Philadelphia was where legend says businessman Charles Darrow dreamed up the iconic board game in 1933 (he didn't, he patented it - it was invented in 1903 by Elizabeth Magie
of Washington DC, but that's another story).
and Margaret MacGregor Magie, and his daughter, Mary Elizabeth Magie
It started in 1903 when Elizabeth Magie
invented a real estate game called "The Landlord's Game.
Erbyn chwilio, mae'n debyg mai yn yr Unol Daleithiau, yn ystod y "Great Depression" yn 1935 y cafodd ei chreu, a hynny drwy ddwyn syniad Crynwraig o'r enw Elizabeth Magie
oedd wedi cael patent ar gem o'r enw "The Landlord's Game" yn 1904.
He fills his narrative with fascinating characters, such as Elizabeth Magie
Phillips, creator of The Landlord's Game, who saw her invention as a way of winning folks over to the crank ideas of single-tax enthusiast Henry George; Columbia University economist Rexford GuyTugwell, who used Phillips' game as a teaching tool and who, as a member of Franklin Roosevelt's New Deal "Brains Trust," pushed for "a full state-administered economy" during the Depression; and the unemployed plumber and "ordinary American" Charles B.
The italics are mine, and the game probably can be traced to Elizabeth Magie
Philips decades before, to be later developed as Atlantic City monopoly, a board game played by Quaker ladies and gentlemen in the Philadelphia area.
16 MONOPOLY: Invented in 1904 by Elizabeth Magie
as a piece of anti-capitalist propaganda.