Mushroom Kingdom is the peaceful Princess Peach's domain as well as the home of the Toads species and coveted by Bowser's evil home and domain known as Koopa Kingdom.
This kingdom have various landscapes include: plains, waterfalls, seaside, snows, mushroom yard, deserts and forests. Before of Mario and Luigi arrival, this kingdom was undefended and Bowser's army easily invade kidnapping the princess in her domain even be freed by plumbers.
After of Mario games, Mushroom Kingdom became allies with other kingdoms and land when the plumbers warriors freed same from Bowser's rule. Even today that kingdom have trouble with Koopa Kingdom after of ruler's first defeat.