Philip Jenkins writes that there is quite a bit of evidence that World War I soldiers were quite a bit more attuned to the supernatural than is often portrayed:
Numerology came into its own, as soldiers tried to calculate the war’s end by adding together the digits in special dates such as the beginning and end of the war of 1870–71. One popular attempt cited by Bächtold-Stäubli predicted the end of the current war as November 11, 1915—an impressive coincidence in terms of the month and day, although off by three years on the actual year. The prophecy demonstrates the widespread expectation that such a war could not conceivably last more than a year or so, which helps to explain the stupefied despair that resulted as it dragged on into its fourth and fifth years.
Catholics in particular had access to a rich arsenal of protective supernatural resources, in the form of rosaries and holy medals. A German soldier tasked with burying the dead noted that most of the soldiers bore a medal of the Immaculate Virgin. Devout Catholics wore the scapular, a pair of simple holy images worn over the chest and back and tied together with light woolen cloth over the shoulders. As scapulars were believed to give protection, from 1914 they became hugely popular among the soldiers and sailors of all the fighting nations.
Whether French or German, Irish or Austrian, Catholic groups sent scapulars and holy images to the fighting forces, and anecdotal evidence suggests these were widely accepted, even by individuals whose peacetime politics might have been strongly anti-religious. Protestant soldiers too developed a real affection for crucifixes and the protection they could afford. French Catholic papers delighted in reporting miracles attributed to scapulars and sacred images—of units escaping casualties during artillery barrages, of vital supplies kept safe by the Sacred Heart. Orthodox Russians, Romanians, and Serbs followed their own traditions of supernatural intervention, commonly by the Virgin or the saints.
Even these resources proved inadequate for believing families who sought to equip their menfolk with still stronger spiritual weapons. Bächtold-Stäubli tells of German mothers and wives pronouncing ritual verses and spells before sending men to the front. They even gave them a Schutzbrief, a heaven-sent letter of protection, in a model that would not have been out of place in the Thirty Years War.