Some addenda and expansions to my comment above:

1. The Philistines existed before the Hebrews - the Children of Israel - arrived in the Land of Canaan according to the Hebrew Biblical narrative. They occupied the territory roughly equivalent to modern day Gaza which was adjacent to Canaan. The Philistines continued to wage war with the Israelites for centuries. (The battle between the future king David and the Philistine Goliath the most famous representation if it). The Philistines may be coeval with or gave been allied with the more northern coastal nation of the Phoenicians (who occupied roughly the region from modern Haifa/ Acco to Lebanon). The Phoenicians brought the phonetic alphabet (invented in south Sinai or Canaan by most accounts circa the 14th-13th c BCE) to Greece in the 8th c BCE.

Consequently, from the Greco-centric and thus standard Western view, Philstinia (Palestinie) was an established ancient kingdom to the East, much more prominent than the Kingdom of Israel which, although it had a treaty with the Davidic Dynasty in Israel (10th c BCE), was more remotely connected to the Greeks. That may be, one might hypothesize, why the region is more strongly identified with the name “Palestine” than “Israel” at least in the imagination of Hellenistic and later Roman cultures.

Nonetheless, the Romans renamed Judaea “Palestine” after they crushed the Jewish rebellion in 70 CE as a deliberate humiliation and act of erasure.

2. My original answer is too compressed. The Romans under General Pompey conquered Israel in 63BCE, annexing it as the “province of Judaea.”

They installed Herod as a king in 33 BCE and promoted Judaea to a “client” state. The native Jews fought several rebellions throughout Roman occupation of Israel/Judaea, finally provoking the Romans by waging all-out war against them, in 66 CE, which was put down harshly by Vespasian. The Romans killed and in some cases openly martyred a very large number of Jews, destroyed the Temple in Jerusalem, and enslaved or dispersed ( thus the ”Diaspora “) most of those Jews who survived.