Ok, the Peanuts had some cultural cache in the 70/80s based on TV specials, marketing campaigns.
Try 'worldwide phenomenon' from the 1950s on. In 1965, the first year of the "Charlie Brown Christmas" special, it was seen by 45% of the American television audience - an audience share unheard of today. It's aired every year since.
Calvin & Hobbes for a few years after that.
Calvin & Hobbes was very popular from 1985-1995, when it was syndicated, and enjoyed a life in books after that. There were even translations printed in Asia.
Also popular during the 1980s: The Far Side, Garfield, Doonesbury, and Bloom County.
But has anyone turned the comic section of their newspaper since the Eisenhower administration?
Eisenhower was president during most of the 1950s. We're talking 1960s-1980s here.