Rashi on Zechariah
for the one to whom she looked was ashamed For [Ashkelon] relied on Tyre, which was the head of the sons of Esau, and Ekron, too, belonged to Edom, as our Sages said in tractate Megillah (6a): “Ekron shall be uprooted (Zeph. 2:4).” This is Caesarea, which belongs to Edom, and it originally belonged to the Philistines.