'On Vengeance'

That was how the Handa-Ombal war began. An Ombal man found that his garden had been wrecked by a pig. He claimed that the offending pig belonged to a certain Handa man, who denied it. The Ombal man became angry, demanded compensation, and assaulted the Handa pig owner when he refused. Relatives of both parties then joined in the dispute, and soon the entire membership of both clans—between four and six thousand people—was dragged into a war that had now raged for longer than Daniel could remember. He told me that, in the four years of fighting leading up to Soll’s death, seventeen other men had been killed.

Jared Diamond on vengeance, in the New Yorker. Via MeFi.