What did Historians think their cities were destroyed either by undersea or by invaders called the?

Historians have often speculated that certain ancient cities were destroyed either by undersea catastrophes, such as earthquakes and tsunamis, or by invaders known as the "Sea Peoples." These Sea Peoples, a confederation of naval raiders, are believed to have contributed to the collapse of several civilizations in the Eastern Mediterranean during the late Bronze Age. The combination of natural disasters and invasions likely led to significant societal upheaval, resulting in the decline or fall of these cities.