In the Fall of 1857, some 120 California-bound emigrants were killed in lonely Mountain Meadows in southern Utah; only eighteen young children were spared. The men on the ground after the bloody deed took an oath that they would never mention the event again, either in public or in private. The leaders of the Mormon church also counseled silence. The first report, soon after the massacre, described it as an Indian onslaught at which a few white...