Biblical Philistines in the North and South

As these Biblical quotations (NRSV) illustrate, the Bible refers to the Sea Peoples in the north as well as the south as Philistines:

Judges 15:9–16

Then the Philistines came up and encamped in Judah, and made a raid on Lehi. The men of Judah said, “Why have you come up against us?” They said, “We have come up to bind Samson, to do to him as he did to us.” Then three thousand men of Judah went down to the cleft of the rock of Etam, and they said to Samson, “Do you not know that the Philistines are rulers over us? What then have you done to us?” He replied, “As they did to me, so I have done to them.” They said to him, “We have come down to bind you, so that we may give you into the hands of the Philistines.” Samson answered them, “Swear to me that you yourselves will not attack me.” They said to him, “No, we will only bind you and give you into their hands; we will not kill you.” So they bound him with two new ropes, and brought him up from the rock.

When he came to Lehi, the Philistines came shouting to meet him; and the spirit of the Lord rushed on him, and the ropes that were on his arms became like flax that has caught fire, and his bonds melted off his hands. Then he found a fresh jawbone of a donkey, reached down and took it, and with it he killed a thousand men. And Samson said,

“With the jawbone of a donkey,

heaps upon heaps,

with the jawbone of a donkey

I have slain a thousand men.”