The word philistine is in fact a neologism. Its application to the ignorant and those of little culture stems from the word philister as used from the seventeenth century by German university students to denote common townspeople. The word probably "travelled" to America with German emigrants and entered the language there along with zeitgeist, before returning to British shores in the Americanised form - philistine - circa 1815.
The reputation of the Philistine people has suffered immeasurably as a result. They deserve a better, and more informed, press if one of history's great wrongs is to be put right.