The original Israelite invasion under Joshua leveled the city and exterminated its people, whether its then name was "Urusalim" or whatever it was-- it was a Canaanite (Hamitic) city.
The "Jebusites" were just a recent people, just a clan, an extended family, of mixed non-Jewish origin who moved/inwandered into the ruins of the city in the interim, till David found it worthwhile to dispossess them. Their tenure there was not only not the original one, but was post-Joshua! They had been there some 200 years at the most, when David drove them and their weak, primitive village from the site and made it the site of his capital city.
The occupation of the site dates from some 5000 years ago (3000 BC), and there was definitely a (small) city there at the dawn of history, as this passage fails to say. It also was considered holy, and its king a "priest of the Most High God" in c2150 BC when Abraham visited the area and gave tithes to its then king, Melchi-zedek "King of Righteousness."
Neither the Jebusites, nor any other Canaanites, were Semites, as this article says, but were a Hamitic people-- Canaan was a descendant not of Shem, but of Ham!
The coastal area occupied by them, including the present Gaza strip and up through present Tel-Aviv, and extending inland some 15-20 miles, was called "Pleshet" in the Bible.
This people was under constant attack by the Jews under the later judges such as Samuel, then by Saul who battled them to a standstill, then by David who decimated them, and finally by Solomon who killed off the last Philistines some 940 BC.
It is still debated what the exact ethnic origin of these people were, but they were tall, blue-eyed blond "Nordics" not speaking a Greek tongue, ...best guesses today suggest they may have been of Etruscan or Hittite origin, but that just pushes back the question, to ask "Who were the Hittites or Etruscans?" LOL.
We have their pictures, they were expert seamen, we even have snatches of their language, that is how we can know it was not (AFAIK) Greek.
Until Yasser Arafat, no one alive on the earth had been a "Pleshti", plural "Pleshtim"---for some 2900 years! In view of the fate seen for this people in Isa. 14 and in Zechariah, Joel 3, etc. it is ironic that Yasser chose to name himself and the "people" he invented out of Arabs who had FTMP recently come in to work for the Jews...after an ancient people whom the Jews had exterminated!
When the Roman general Pompey conquered Eretz Yisroel about 62 BC, he added that coastal strip to the much larger Roman province of Syria, and the little dangling strip we call "Israel and the Territories" he called "Syria Palestensis," or "Syria of the Philistines," a people still remembered for their ferocity even though they had been extinct for 900 years.