The Egg McMuffin became McDonald’s first nationally advertised breakfast sandwich.
Herb Peterson, a McDonald’s franchise owner in Santa Barbara, California, created the sandwich in the early 1970s. It used an English muffin, a freshly cracked egg, Canadian bacon, and cheese, giving the chain a portable breakfast item that resembled an eggs Benedict in simplified form.
The sandwich was tested locally before McDonald’s expanded it across the United States in 1975. Its success helped establish breakfast as a major part of McDonald’s brand identity and menu strategy, rather than merely a limited local offering.
The Egg McMuffin is often confused with the launch of the entire McDonald’s breakfast menu. It was the key signature product that helped nationalize breakfast, but McDonald’s later added hotcakes, sausage, hash browns, and many regional items. Its branding also reinforced the company’s familiar “Mc” naming pattern.