McDonaldland first appeared in McDonald's advertising in 1971.
The campaign created a colorful fictional world populated by characters such as Ronald McDonald, Grimace, the Hamburglar, Mayor McCheese, and Birdie the Early Bird. It gave McDonald's a connected cast of recognizable figures rather than relying on Ronald alone.
McDonaldland was designed especially to appeal to children and became a major part of the company's television, in-store, and promotional branding. The characters appeared in commercials, playground designs, packaging, and licensed merchandise.
The campaign is sometimes confused with Ronald McDonald's earlier debut, which occurred in the 1960s. Ronald existed before the wider McDonaldland setting, while McDonaldland supplied the shared fictional environment and its supporting characters.