McDonald's launched the McDonaldland advertising world in 1971.
McDonaldland presented McDonald's products and mascots in a colorful fantasy setting aimed primarily at children. Ronald McDonald served as the central character, joined by figures such as Grimace, the Hamburglar, and Mayor McCheese. The campaign turned restaurant branding into a recurring fictional world rather than a series of unrelated advertisements.
The characters helped McDonald's create a recognizable cast that could appear across television commercials, packaging, store displays, and promotional products. Their designs and roles changed over time, so early versions do not always look like the characters remembered from later decades.
McDonaldland is sometimes confused with the debut of Ronald McDonald, which occurred earlier in 1963. The 1971 date refers to the larger branded setting and ensemble of characters. The campaign became one of the most distinctive examples of children's fast-food marketing.