Which McDonald’s character was created to promote the Shamrock Shake?

Uncle O’Grimacey was the McDonald’s character created to promote the Shamrock Shake.

The green, leprechaun-like character was introduced in 1975 as the uncle of Grimace. His role connected McDonald’s seasonal Shamrock Shake with St. Patrick’s Day imagery and the drink’s distinctive green color.

Uncle O’Grimacey is sometimes mistaken for Grimace himself, but the two were presented as separate characters. Grimace became a broader McDonaldland figure, whereas Uncle O’Grimacey was chiefly associated with the annual shake promotion.

The character illustrates how McDonald’s used fictional personalities not only for its core menu but also for limited-time products. The Shamrock Shake was first introduced in 1970, several years before Uncle O’Grimacey appeared.