Adding to Jim Davila’s post on the Philistines, among others, there’s another interesting tidbit to add.
The online Oxford English Dictionary’s etymology for Philistine refers us to the etymology for philister:
The use of the word in this sense is said to have originated at Jena in 1693, in a sermon from the text Philister über dir, Simson! ‘The Philistines are upon you, Samson!’ (Judges 16:9, 12, 14, 20) preached by Pastor Götze at the funeral of one of the students who had been killed in a quarrel between townspeople and students, but it was app. in fact already in use in Jena in 1687.
The definition for philister is “An unenlightened or uncultured person; = PHILISTINE n. 3; (spec. in German universities) a townsperson, a non-student.” The earliest usages included in both entries date to the 1820s, however, so Pastor Götze is not to receive credit for introducing the connotation of Philistine as boor to the English. The Hebrew Bible itself also cannot be held accountable for this usage, as there’s no trace of the derogatory reuse of פלשתי in reference to those who are not ethnic Philistines. It’s not too surprising that later familiarity with the Old Testament along with some extrabiblical supersessionist ideas about Israel’s ancient neighbors led to this connotation among Europeans who considered themselves several rungs further up the ladder than even the Israelites. Fun stuff!