I read the book "1177 BC: The Year Civilization Collapsed". There may have been an accompanying weather event/crop failure, which made things especially hard on walled cities. The "Sea Peoples" may have been a loose confederation of separate Greek, Italian, and Semitic tribes (perhaps the Phoenicians and Biblical Jews) , all three learning to build ships and use seige tactics. The fall of Troy has been dated to this time, as have various Biblical battles (which apparently drove out what remained of the Canaanites). The Assyrian (Middle Empire) and Armenian Empire (Nairi Tribal Confederation) of the time seemed less affected (further from coastal waters, harder to sack from ships), or perhaps they assisted in the "sacking"?