Here the Philistines appear for the first time in the book, which reflects a time after Judges 1:34, where the Amorites (local Canaanites) are mentioned as living in the coastal area that would later become the Philistine territory. Also, Judges 1:18, referring to Gaza, Ashkelon, and Ekron, knows nothing of a Philistine presence there.
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3 These are the nations: the five lords of the Philistines and all the Canaanites and the Sidonians and the Hivites who lived on Mount Lebanon, from Mount Baal-hermon as far as Lebo-hamath.