'Philistine Rulers' in the Bible

So David received them and assigned them to be officers over troops. Some of the descendants of Manasseh joined David when he was going to fight against Saul, accompanied by the Philistines. Even so, David was of no help to them, because the Philistine rulers were counseled to send him away. They told themselves, "He's going to go over to his master Saul at the cost of our heads."