The general Levant area is historically a really important region strategically/geopolitcally. It is situated between 3 continents (Europe, Asia and Africa). It has a big coastline with plenty of natural harbours. It is surrounded by big mountain ranges and deserts, which make it very defensible from the outside. It is near important trade routes such as the Persian Gulf, the Red Sea and the Silk Road and controls their passage into the Mediterranean. It has relatively fertile soil and plenty of access to drinking water, while the East Mediterranean provides a very good source of seafood. It has some amount of oil and minerals. So whoever controls the whole of it can easily exhert a very strong influence in the region economically, politically and militarily. Hence it's always been a big target of imperialist/colonialist powers.
It's no wonder that only 2 local peoples managed to ever be in charge for a significant amount of time, throughout history: The Phoenicians in ancient times and the Arabs in Medieval times. Someone always tries to conquer it, because just by looking at a map can tell you how important it is.
The Levant itself is crisscrossed by deserts and mountains, with a very sparsely populated interior, so whoever conquers it always has trouble holding it for long. Since Roman times, the suppression tactic of conquerors has always been to divide and conquer. The geography and importance of the region means there's a bunch of ethnically, religiously and culturally different people who live together in and near the big population centers. These divisions have historically been taken advantage of to pit them against each other and prevent their unity.
The Israel-Palestine conflict is just the effects of the last attempt by the so-called Great Powers to keep the region divided. The way they split it up after accepting to abandon their colonial governance of it and then the accession to Zionists to colonize it, has created what we see now.
The Ottomans had been trying something similar with Syria in the 1800s (pitting the previously friendly Christian and Muslim population against each other), which they tried to revert unsuccessfully shortly before losing it to France and England after WW1 (https://en.m.wikipedia.org/wiki/1860_civil_conflict_in_Mount_Lebanon_and_Damascus).