pacification (n.)

"a setting at peace," mid-15c., pacificacioun, from Old French pacification "act of making peaceful" (15c.) and directly from Latin pacificationem (nominative pacificatio) "a peace-making," noun of action from past-participle stem of pacificare "to pacify" (see pacify). As "military operation designed to secure local cooperation in an area where enemy forces are thought to be active," by 1946.