The Philistines—perennial enemies of the Israelites in the Bible—were one of several tribes of “Sea Peoples” from the Aegean who invaded and colonized the eastern shores of the Mediterranean in the 12th century B.C.E. While the Philistines were concentrated in what is now the Gaza Strip, other tribes lived along the northern coast of Israel as well as in Syria and Lebanon. They were a force to be reckoned with:
In wave after wave of land and sea assaults [the Sea Peoples] attacked Syria, Palestine, and even Egypt itself. In the last and mightiest wave, the Sea Peoples, including the Philistines, stormed south from Canaan in a land and sea assault on the Egyptian Delta. According to Egyptian sources, Ramesses III (c. 1198–1166 B.C.E.) soundly defeated them in the eighth year of his reign. He then permitted them to settle on the southern coastal plain of Palestine. There they developed into an independent political power and a threat both to the disunited Canaanite city-states and to the newly settled Israelites.
Read more on Bible History Daily: http://www.biblicalarchaeology.org/daily/ancient-cultures/ancient-israel/the-philistines-to-the-north/