McDonald's fictional children's advertising world was called McDonaldland.
McDonaldland appeared in television commercials and promotions beginning in the 1960s. It turned the restaurant brand into a colorful setting populated by recurring characters, including Ronald McDonald, the Hamburglar, Mayor McCheese, and Grimace.
The name is sometimes confused with the individual characters or with Ronald McDonald's home, but McDonaldland refers to the broader fictional world. That distinction matters because the campaign operated as an interconnected setting rather than a single mascot advertisement.
McDonaldland gave McDonald's a distinctive family-oriented identity during a period when fast-food chains were investing heavily in memorable television characters. Several characters later became strongly associated with the brand, even as the company gradually reduced the fictional world's role in mainstream advertising.