The Egg McMuffin was introduced widely in 1975, eight years before the Chicken McNugget in 1983.
The Egg McMuffin was a creation of Herb Peterson, who ran a McDonald’s in Santa Barbara in 1972. It was introduced to the national menu in 1973.
Chicken McNuggets was introduced in select markets in 1981, then debuted nationally in 1983.
The instant they debuted in 1983 Chicken McNuggets were a global phenomenon. Within months, the bite-size chicken pieces made McDonald’s, a hamburger restaurant, the second biggest retailer of chicken on the planet, trailing behind only KFC.Chicken Nugget Secrets: Science, Health, Money, McDonald’s | Time