Benedict XV, whose papacy started just after the War began, called it "the suicide of civilized Europe." Certainly, the photographs depict a world which has not only disappeared but is almost unrecognizable to us. Some photos, like this one, seem surreal.
meeting French General Albert Baratier (on horseback)
as General Joffre, commander of French forces looks on, 1915 AD
Benedict called for a Christmas truce in 1914 but was ignored. Benedict attempted to mediate peace in 1916 and again in 1917, but Germany rejected these efforts as "insulting," while Clemenceau called them anti-French.
By the time the Armistice took effect at 11:11 on November 11, 1918, 37 million civilians and soldiers had been killed or wounded.