On May 1st, Carl Perkins' "Blue Suede Shoes" peaked at #4 on the Billboard Top 100 chart (it would reach #2 on the Jukebox chart). It is ironic that at the same time, Elvis Presley had his first number one record, "Heartbreak Hotel." While Elvis's career was taking off into the stratosphere with his new contract at RCA, Sam Phillips at Sun Records was thinking he'd be okay with his new star, Perkins. But it wasn't to be. Perkins would never come close to his success with "Blue Suede Shoes." Elvis also recorded "Blue Suede Shoes" and performed it on national television. Originally released as part of an EP ("extended play" record with four cuts, two on each side), it would eventually be released as a single in September (#20). Perkins was in a car accident in March and it prevented him from promoting his career with television or public appearances. The result was that most people identify "Blue Suede Shoes" with the by far better known Presley.
"The Poor People of Paris," "Hot Diggity," "Lisbon Antigua," and "Rock and Roll Waltz" were all former number ones in the top twenty the week of May 1st, while "Moonglow/Theme From Picnic" by Morris Stoloff was on its way to the top.
To use the current vernacular, rock and roll music was going "viral" in 1956, but it still had a minority representation in May as the only top ten song other than "Heartbreak Hotel" and "Blue Suede Shoes" in the genre was the doo-wop sound of The Platters with "Magic Touch."
Also, you might notice multiple recordings of the same song: "Moonglow" and "Why Do Fools Fall in Love." That was a common occurance in the mid 1950's.