I was just glancing through The Survey of Western Palestine, written in 1878.
The first thing to notice is the title; Western Palestine is the parts that are west of the Jordan River, as opposed to Eastern Palestine, which had its own survey. I have yet to find a single Palestinian Arab willing to say that they claim Jordan as part of their ancestral land of Palestine. (Just as none of them claimed the West Bank or Gaza to be theirs before 1967. Funny how Arab claims always coincide with Jewish control.)
We see that Jews were immigrating in droves:
But - so were Arabs. Here is a description of new building in mostly Arab towns, saying where one group came from explicitly:
This might explain why so many Arab residents of Jaffa decided to flee to Egypt in 1948, as opposed to the east or to the north. They already came from there!
Not that this is any secret to the Arabs themselves. But they won't admit that in English.