Samaria, the city, was the capital of the northern Kingdom of Israel from the 9th century BCE. It was never a city in "Palestine," and in fact the phrase "Biblical Palestine" is essentially an oxymoron. (One can find found a couple of examples of that phrase in pre-1948 books but they were using Palestine as a shortcut to refer to the kingdoms of Israel and Judah, Here's an example:)
But nowadays to refer to a Biblical-era town as being in "Palestine" is not accurate. You can refer to Biblical Judea or Biblical Israel or Biblical Moab or Biblical Hauran, but not Biblical Palestine; it simply makes no sense since Biblical events (at least in the Jewish Bible) predated anyone calling the area "Palestine."
No one says "Biblical Jordan."Abraham may have been born in present-day Iraq but the term "Biblical Iraq" would be nonsense. "Biblical Palestine" is just as bizarre and on some level it is a (possibly subconscious) attempt to sever the ties between Jews and their ancient homeland.
(h/t Harris)
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