As audiences in the East were used to science finding fantastic new things, it hardly seemed impossible to a person in the 19th century that the country had once been inhabited by giants, or that ancient, incredible civilizations could still lie undiscovered in the vast west. Some newspaper writers were more than happy to simply make great discoveries up, and readers just as happy to take them at their word.
An epithet is a byname, a characterizing word or phrase that accompanies or occurs in place of the name of a person or thing. Historically, some have been unfortunate- just ask Alfonso the Slobberer or Eystein Foul-Fart.