Well where in the world did I come up with Pergamos? I must re-read THE ILIAD again.
I think just about any city of any size in the Aegean, Eastern Mediterranean or Ionian Sea were mentioned by Homer probably to make the story more interesting to the people living in those areas.
Dunno, the Pergamos was apparently the region around Pergamum, and mentioned (probably not favorably) in Revelation. :’)
https://www.google.com/search?q=The+Pergamos