After the death of both Achilles and Hector, and the fall of Troy, Neoptolemus captured the newly widowed Andromache for his concubine and went to rule in Epirus.
After Neoptolemus's death, some sources say that Andromache returned to Asia Minor with her youngest son, Pergamus, although this is probably a later addition to the legend.
Andromache's descendants would include the royal family of Epirus (and thus Olympias, the mother of Alexander the Great), and Pergamus's line would include Attalus, the forefather of the Attalid rulers (although not a king himself and considered of common stock).
It does not appear to have been a major part of Attalid propaganda (unlike their claimed link to the hero Telephus), but at least one small heroon (shrine) in Pergamon was dedicated to Pergamos Ktistes, probably built in the 3rd century BC.
The King James Version of the Bible uses the name "Pergamos" in Revelation 2:12 for the seat of one of the seven churches of Asia, a city that modern translations call Pergamum or Pergamon.