victim: Amalekites
Amalekites captured people and cattle from David's home (Ziklag) when David was away - going to fight with Philistines against Saul - so David persiut Amalekites until he found them and killed them all except 400 men who fled. And he saved his captured people and his wifes too (Ahinoam of Jezreel and Abigail, the widow of Nabal of Carmel)