As these Biblical quotations (NRSV) illustrate, the Bible refers to the Sea Peoples in the north as well as the south as Philistines:
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.”
1 Samuel 17:4–7, 48–49
And there came out from the camp of the Philistines a champion named Goliath, of Gath, whose height was six cubits and a span. He had a helmet of bronze on his head, and he was armed with a coat of mail; the weight of the coat was five thousand shekels of bronze. He had greaves of bronze on his legs and a javelin of bronze slung between his shoulders. The shaft of his spear was like a weaver’s beam, and his spear’s head weighed six hundred shekels of iron; and his shield-bearer went before him. […] When the Philistine drew nearer to meet David, David ran quickly toward the battle line to meet the Philistine. David put his hand in his bag, took out a stone, slung it, and struck the Philistine on his forehead; the stone sank into his forehead, and he fell face down on the ground.
1 Samuel 31:8–13
When the Philistines came to strip the dead, they found Saul and his three sons fallen on Mount Gilboa. They cut off his head, stripped off his armor, and sent messengers throughout the land of the Philistines to carry the good news to the houses of their idols and to the people. They put his armor in the temple of Astarte; and they fastened his body to the wall of Beth-shan. But when the inhabitants of Jabesh-gilead heard what the Philistines had done to Saul, all the valiant men set out, traveled all night long, and took the body of Saul and the bodies of his sons from the wall of Beth-shan. They came to Jabesh and burned them there. Then they took their bones and buried them under the tamarisk tree in Jabesh, and fasted seven days.