Which McDonald's character was known as the chain's pirate mascot?

Captain Crook was McDonald's pirate mascot.

Captain Crook was one of the characters associated with McDonaldland, the fictional advertising setting used to give McDonald's products and restaurants a shared story world. His pirate costume and exaggerated manner made him visually distinct from characters such as Grimace and the Hamburglar.

The character was especially connected with Filet-O-Fish advertising. That association made Captain Crook part of the way McDonald's gave individual menu items their own personalities and promotional identities.

Captain Crook is sometimes confused with Officer Big Mac, another character from the same advertising world. The two belonged to the same broad cast, but Captain Crook was the pirate, while Officer Big Mac was presented as a law-enforcement character.