According to scripture, the Philistines were not native to the Levant, but were a very recent addition to the area prior to the Conquest period.
The Bible says they are from Caphor, which is generally translated as the island of Crete.
According to secular history, a group of “sea peoples” landed in Syria in the 15th century BC, and fought there way down to Megiddo, where they fought a battle with the Egyptians and lost. (Megiddo is translated Armageddon in Greek)
After the loss, the Egyptians reported them to the Levant, but continued a trade relationship with them.
I assume these are the Philistines based on geography and timeline.
The mountain of Thera erupted in mid 1600s BC, destroying Akrotiri and causing tsunamis on Crete, destroying their capital of Knossos.
This, along with a string of recorded earthquakes afterward likely led to Crete being evacuated.