Some people thought it was too 'sexually explicit' at the time.
From Graceland…
Today marks the day Elvis famously performed "Hound Dog" on "The
Milton Berle Show" and stirred up quite a frenzy. On June 5, 1956,
Elvis set his guitar to the side and performed what came to be known
as one of the most controversial performances in television history.
The provocative hip-swinging dance moves caused a national scandal and
set the stage for the King of Rock 'n' Roll's place in history.
His performance of "Hound Dog" drove the kids in the audience wild and
disgusted the press and some of the adult viewers. His sexy moves and
black-influenced sound was condemned by certain factions of the
“morally concerned” establishment and the religious community, but his
seemingly unstoppable popularity continued to grow to new heights.