Beatlemania hit the U.S.A. in full force after John, Paul, George and Ringo played 'The Ed Sullivan Show' on Feb. 9, 1964 Rachel DeSantis is a senior writer on the music team at PEOPLE.

This consensus was reached (in the U.S., at least) just after 8 PM on Feb. 9, 1964, when the Beatles made their historic appearance on The Ed Sullivan Show. More than 73 million people watched on ...