The emperor Nero is a caricature of Charles Laughton's portrayal of King Henry VIII in Young Bess (1953).
The tail fins on Nero's chariot are patterned after those on the 1954 Cadillac Coupe DeVille.
The caption at the beginning says "ROME 54 A.D." A.D. 54 was the year Nero became emperor of Rome -- 1901 years before 1955, when the cartoon was made and released.
The U. S. Defense Highway system was being constructed at the time of this short, and billboards proclaiming this were seen across the country. The sign early in the short is a send up of these, and mentions the Appian Way, one of the Roman empire's main thoroughfares.