What advertising character-filled world did McDonald's launch in 1971?

McDonald's launched the character-filled advertising world McDonaldland in 1971.

McDonaldland presented McDonald's products and mascots as part of a colorful fictional setting. Ronald McDonald served as the central character, while figures such as Mayor McCheese, Grimace, and the Hamburglar helped create a recognizable cast for children's advertising.

The campaign was developed for television and other promotional uses, giving McDonald's a distinctive fantasy setting rather than relying only on restaurant imagery or product demonstrations. It became one of the most important parts of the company's character branding during the 1970s.

McDonaldland is sometimes confused with the name of a restaurant or a real theme park. It was primarily a fictional advertising universe, though McDonald's later used McDonaldland-themed playgrounds and promotions at restaurants.