McDonaldland was the character-filled fantasy world introduced in McDonald's advertising during the 1970s.
The setting gave Ronald McDonald a larger cast of friends and adversaries, including Grimace, the Hamburglar, Mayor McCheese, and Birdie the Early Bird. These characters appeared in commercials, in-store materials, and promotional products, turning the restaurant brand into a recognizable fictional environment for children.
McDonaldland was not a real theme park or a separate restaurant chain. It was an advertising universe built around food-related characters and playful locations. The concept helped McDonald's connect its mascot program with the Happy Meal and other child-focused promotions.
The characters changed over time, and some were retired or used less often. That evolution can make individual debut dates difficult to identify, but the name of the overall fictional world is consistently McDonaldland.