McDonald's fantasy world of advertising characters was called McDonaldland.
McDonaldland was introduced in 1971 as a colorful setting populated by characters connected to McDonald's products and restaurant imagery. Ronald McDonald served as its central figure, alongside characters such as Mayor McCheese, Grimace, and the Hamburglar.
The world gave McDonald's a consistent storytelling framework for television commercials, packaging, playgrounds, and promotional materials. Instead of advertising only individual menu items, the company could present visits to McDonald's as an imaginative family experience.
McDonaldland characters changed over time, and some were retired or redesigned. This sometimes causes confusion between the name of the fictional setting and the names of its characters. McDonaldland is the umbrella world; Mayor McCheese, Grimace, and others are inhabitants of that world.