mid-15c., persecuten, "to oppress for the holding of an opinion or adherence to a particular creed or mode of worship," from Old French persécuter "pursue, torment, open legal action" (14c.) and directly from Latin persecutus, past participle of persequi "to follow, pursue, hunt down; proceed against, prosecute, start a legal action," from per "through" (from PIE root *per- (1) "forward," hence "through") + sequi "follow" (from PIE root *sekw- (1) "to follow"). Related: Persecuted; persecuting.